Mileage

[Mike]

What kind of MPG can I expect from a Fiero?
Are the 4 cyl any better than the 6?

[PePe_LePu_For2]

Mike,
I can't comment on the 4 cylinder mileage because its been 20 years
since I've owned one, but I can tell you what I've been able to get with my
88 GTs. My current car has done 32 on the freeway at least twice so far.
Back when I had my first 88 GT the speed limit was still 55 MPH. Under those
conditions I was able to squeeze 34 out of it once. The conditions of these
mileage records were... Filling up at a gas station near a freeway on ramp,
smoothly gliding out onto the freeway, slowly ramping up to 55/65 in the far
right hand lane, and finally setting the cruise control to the posted limit.
Then I would just take it easy until it was time to refill the tank.
In regular daily commute/city driving you find yourself struggling to
get as little as 28 MPG with a V6. I mostly get around 24 - 26.

Martin

Post by Mike
What kind of MPG can I expect from a Fiero?
Are the 4 cyl any better than the 6?

[John Craker]

The ultimate mileage fiero has got to be an 87/88 4cyl 5spd (not auto!!!!).

I pulled a bit over 40mpg on a highway run.

City was worse of course, but still not as bad as say an '86 GT with an auto
and A/C (about the worst combo... hehe)

Post by PePe_LePu_For2
Mike,
I can't comment on the 4 cylinder mileage because its been 20 years
since I've owned one, but I can tell you what I've been able to get with my
88 GTs. My current car has done 32 on the freeway at least twice so far.
Back when I had my first 88 GT the speed limit was still 55 MPH. Under those
conditions I was able to squeeze 34 out of it once. The conditions of these
mileage records were... Filling up at a gas station near a freeway on ramp,
smoothly gliding out onto the freeway, slowly ramping up to 55/65 in the far
right hand lane, and finally setting the cruise control to the posted limit.
Then I would just take it easy until it was time to refill the tank.
In regular daily commute/city driving you find yourself struggling to
get as little as 28 MPG with a V6. I mostly get around 24 - 26.
Martin

Post by Mike
What kind of MPG can I expect from a Fiero?
Are the 4 cyl any better than the 6?

[Phil Randolph]

I've done 40-41 on few road trips (flat country and steady highway
speeds) in our 88 4 cyl 5 sp

Post by John Craker
The ultimate mileage fiero has got to be an 87/88 4cyl 5spd (not auto!!!!).
I pulled a bit over 40mpg on a highway run.
City was worse of course, but still not as bad as say an '86 GT with an auto
and A/C (about the worst combo... hehe)

Post by PePe_LePu_For2
Mike,
I can't comment on the 4 cylinder mileage because its been 20 years
since I've owned one, but I can tell you what I've been able to get with my
88 GTs. My current car has done 32 on the freeway at least twice so far.
Back when I had my first 88 GT the speed limit was still 55 MPH. Under those
conditions I was able to squeeze 34 out of it once. The conditions of these
mileage records were... Filling up at a gas station near a freeway on ramp,
smoothly gliding out onto the freeway, slowly ramping up to 55/65 in the far
right hand lane, and finally setting the cruise control to the posted limit.
Then I would just take it easy until it was time to refill the tank.
In regular daily commute/city driving you find yourself struggling to
get as little as 28 MPG with a V6. I mostly get around 24 - 26.
Martin

Post by Mike
What kind of MPG can I expect from a Fiero?
Are the 4 cyl any better than the 6?

[JStricker]

Phil is getting very good mileage (and no, I don't doubt you, I've done it
myself as well, it's just that it doesn't happen often so don't EXPECT it).

Normally, the 5 spd 4 cyl cars will get well over 30 and around 35
The 5 spd 6 cyl cars will get right at 30
The 4 spd 4 cyl cars will get just under 30
The 4 spd 6 cyl or the automatic anything will be doing good to average in
the mid 20's.

The lack of an overdrive really kills almost anything when you have to rev
around 3000 to run 70 and that's what the stock autos and 4 spds do. OTOH,
my Caddy 4.9 with an automatic 4T65E will consistently run 31-33 mpg at 70
mph. If I run closer to 80, it drops down to about 28 or so.

John Stricker

I've done 40-41 on few road trips (flat country and steady highway speeds)
in our 88 4 cyl 5 sp

Post by John Craker
The ultimate mileage fiero has got to be an 87/88 4cyl 5spd (not auto!!!!).
I pulled a bit over 40mpg on a highway run.
City was worse of course, but still not as bad as say an '86 GT with an
auto and A/C (about the worst combo... hehe)

Post by PePe_LePu_For2
Mike,
I can't comment on the 4 cylinder mileage because its been 20 years
since I've owned one, but I can tell you what I've been able to get with my
88 GTs. My current car has done 32 on the freeway at least twice so far.
Back when I had my first 88 GT the speed limit was still 55 MPH. Under those
conditions I was able to squeeze 34 out of it once. The conditions of these
mileage records were... Filling up at a gas station near a freeway on ramp,
smoothly gliding out onto the freeway, slowly ramping up to 55/65 in the far
right hand lane, and finally setting the cruise control to the posted limit.
Then I would just take it easy until it was time to refill the tank.
In regular daily commute/city driving you find yourself struggling to
get as little as 28 MPG with a V6. I mostly get around 24 - 26.
Martin

Post by Mike
What kind of MPG can I expect from a Fiero?
Are the 4 cyl any better than the 6?

[Hank]

My 85 2m4 5 speed 170K miles was getting around 22 mpg I do not do
much hiway driving and its no longer my daily drive.

My new daily drive a 85 GT 6 cyl 4 speed 63K miles still only averages
17 mpg. So how would you go about improving that ?

When I got that car 8 weeks ago I replaced the plugs, cap, rotor, oil
change and gear box oil change and recently replaced the AIC as it was
stalling that stoped. My tire pressure is good there are no error
codes. I even tried for a week to be less lead footed but no change in
mpg.
Hank

Post by JStricker
Phil is getting very good mileage (and no, I don't doubt you, I've done it
myself as well, it's just that it doesn't happen often so don't EXPECT it).
Normally, the 5 spd 4 cyl cars will get well over 30 and around 35
The 5 spd 6 cyl cars will get right at 30
The 4 spd 4 cyl cars will get just under 30
The 4 spd 6 cyl or the automatic anything will be doing good to average in
the mid 20's.
The lack of an overdrive really kills almost anything when you have to rev
around 3000 to run 70 and that's what the stock autos and 4 spds do. OTOH,
my Caddy 4.9 with an automatic 4T65E will consistently run 31-33 mpg at 70
mph. If I run closer to 80, it drops down to about 28 or so.
John Stricker

I've done 40-41 on few road trips (flat country and steady highway speeds)
in our 88 4 cyl 5 sp

Post by John Craker
The ultimate mileage fiero has got to be an 87/88 4cyl 5spd (not auto!!!!).
I pulled a bit over 40mpg on a highway run.
City was worse of course, but still not as bad as say an '86 GT with an
auto and A/C (about the worst combo... hehe)

Post by PePe_LePu_For2
Mike,
I can't comment on the 4 cylinder mileage because its been 20 years
since I've owned one, but I can tell you what I've been able to get with my
88 GTs. My current car has done 32 on the freeway at least twice so far.
Back when I had my first 88 GT the speed limit was still 55 MPH. Under those
conditions I was able to squeeze 34 out of it once. The conditions of these
mileage records were... Filling up at a gas station near a freeway on ramp,
smoothly gliding out onto the freeway, slowly ramping up to 55/65 in the far
right hand lane, and finally setting the cruise control to the posted limit.
Then I would just take it easy until it was time to refill the tank.
In regular daily commute/city driving you find yourself struggling to
get as little as 28 MPG with a V6. I mostly get around 24 - 26.
Martin

Post by Mike
What kind of MPG can I expect from a Fiero?
Are the 4 cyl any better than the 6?

[JStricker]

Last thing first.

For an '85 V6 4 spd that you don't do much highway driving, I'd say you're
doing about average or just a little below, but not much. I don't know of
many V6 4 spd's that will get over 20 in city driving, just not going to
happen.

I'd say that your 4 cyl. with the 5 spd is a little tired. It would
probably do it some good to clean the injector in the TB and also be sure
you set the timing since it's going to have a distributor.

Back to your '85, since you asked how to improve things, I'd start with
double checking everything. If you have access to a good scanner then plug
that in and see what it's showing. Make sure your temp sensor to the ECM is
reading close to what your gauge is reading. Also make sure that your
Intake Air Temp sensor is showing something close to the outside temp. If
these are off, the mixture is off by quite a bit until the ECM goes into
closed loop.

The EGR on these is also prone to some problems particularly getting
carboned up. This problem will NOT set a code. There is nothing there to
tell it that the EGR is leaking or not opening physically. The code is set
by a switch in the EGR solenoid and just because it's sending a vacuum
signal (or not) does not mean the valve is opening (or closing). These are
pretty easy to take off and clean/replace but be careful to not break your
EGR tube, they're like gold to go back to stock.

Naturally, check EVERYTHING. Make sure your brakes aren't dragging, it's a
lot more common than you think. I'd up the air in the tires for city
driving at least 2-3 pounds over what the sticker calls for. Air Filter
clean? Fuel filter clean? I've had good luck cleaning the injectors but I
built my own cleaning tool. A shop can do it on the car and clean the fuel
system very well. Make sure the timing is properly set on the car. If you
have an aftermarket chip ("performance") take it out and put the stock one
back in. For the stock motor, it's a very good chip.

With all that in mind, around town driving kills mileage on a stick shift
car, it really does. There's not much you're going to do to get your
mileage with the 4 spd above 24-25 even on the highway at moderate speeds,
it's just not geared for mileage. You can make sure that EVERYTHING is
right, though, and get everything you can out of it.

If the car were closer, I'd be happy to stick it on my wide band O2 and Snap
On MT2500 Scanner on it so we could go for a drive to see what was going on.

John Stricker

PS: I have now, or have owned/done Fieros with:

Stock 2.8 and auto
3.4 crate motor and auto
4.9L caddy with caddy auto
383 small block Chevy with 5 speed
4 cyl with 4 spd
4 cyl with auto
6 cylinder with 5 speed
3.4 race motor with Isuzu 5 speed from a 4 cylinder

Post by Hank
My 85 2m4 5 speed 170K miles was getting around 22 mpg I do not do
much hiway driving and its no longer my daily drive.
My new daily drive a 85 GT 6 cyl 4 speed 63K miles still only averages
17 mpg. So how would you go about improving that ?
When I got that car 8 weeks ago I replaced the plugs, cap, rotor, oil
change and gear box oil change and recently replaced the AIC as it was
stalling that stoped. My tire pressure is good there are no error
codes. I even tried for a week to be less lead footed but no change in
mpg.
Hank

[Hank]

Yes I replaced all the brake pads and bleed them all off as the front
driver side was really grabbing it better now, air filter is really
clean I will continue to check out the other items. My guess is as it
consistant at 17 mpg all is pretty good my understanding is they realy
were not mpg cars and I really dont care as I love to drive it. My
only concern is if its really under par maybe something is wrong with
it. I dont know if the chip is aftermaker as I said I just got the
car. I have a parts car a 96 maybe I will pull the ECM from it and see
if there is a difference its a 6 with a 4 speed also. I cannot believe
the power difference between the 4 and 6 cyl and I am still having
trouble using te 4 speed vs the 5 speed. I am thinking maybe next
summer finding a 5 speed or even swaping between the 2 cars. My
location is Manchester NH.
My 96 Jag XJ6 I ran it down this summer to L.I. NY it got 25 mpg
highway it usually gets around 17 city.
My web site with my cars
http://mysite.verizon.net/vzeecixb/

Hank

Post by JStricker
Last thing first.
For an '85 V6 4 spd that you don't do much highway driving, I'd say you're
doing about average or just a little below, but not much. I don't know of
many V6 4 spd's that will get over 20 in city driving, just not going to
happen.
I'd say that your 4 cyl. with the 5 spd is a little tired. It would
probably do it some good to clean the injector in the TB and also be sure
you set the timing since it's going to have a distributor.
Back to your '85, since you asked how to improve things, I'd start with
double checking everything. If you have access to a good scanner then plug
that in and see what it's showing. Make sure your temp sensor to the ECM is
reading close to what your gauge is reading. Also make sure that your
Intake Air Temp sensor is showing something close to the outside temp. If
these are off, the mixture is off by quite a bit until the ECM goes into
closed loop.
The EGR on these is also prone to some problems particularly getting
carboned up. This problem will NOT set a code. There is nothing there to
tell it that the EGR is leaking or not opening physically. The code is set
by a switch in the EGR solenoid and just because it's sending a vacuum
signal (or not) does not mean the valve is opening (or closing). These are
pretty easy to take off and clean/replace but be careful to not break your
EGR tube, they're like gold to go back to stock.
Naturally, check EVERYTHING. Make sure your brakes aren't dragging, it's a
lot more common than you think. I'd up the air in the tires for city
driving at least 2-3 pounds over what the sticker calls for. Air Filter
clean? Fuel filter clean? I've had good luck cleaning the injectors but I
built my own cleaning tool. A shop can do it on the car and clean the fuel
system very well. Make sure the timing is properly set on the car. If you
have an aftermarket chip ("performance") take it out and put the stock one
back in. For the stock motor, it's a very good chip.
With all that in mind, around town driving kills mileage on a stick shift
car, it really does. There's not much you're going to do to get your
mileage with the 4 spd above 24-25 even on the highway at moderate speeds,
it's just not geared for mileage. You can make sure that EVERYTHING is
right, though, and get everything you can out of it.
If the car were closer, I'd be happy to stick it on my wide band O2 and Snap
On MT2500 Scanner on it so we could go for a drive to see what was going on.
John Stricker
Stock 2.8 and auto
3.4 crate motor and auto
4.9L caddy with caddy auto
383 small block Chevy with 5 speed
4 cyl with 4 spd
4 cyl with auto
6 cylinder with 5 speed
3.4 race motor with Isuzu 5 speed from a 4 cylinder

Post by Hank
My 85 2m4 5 speed 170K miles was getting around 22 mpg I do not do
much hiway driving and its no longer my daily drive.
My new daily drive a 85 GT 6 cyl 4 speed 63K miles still only averages
17 mpg. So how would you go about improving that ?
When I got that car 8 weeks ago I replaced the plugs, cap, rotor, oil
change and gear box oil change and recently replaced the AIC as it was
stalling that stoped. My tire pressure is good there are no error
codes. I even tried for a week to be less lead footed but no change in
mpg.
Hank

[JStricker]

Hank,

You know, this sucks.

I just got around to checking the group and read your reply. Then I checked
out your webpage. You live in Manchester. My wife and I just got back from
delivering my '80 IHC Scout to it's new owner in Bedford on Tirrell Road.
We stayed at the Courtyard over by the airport. I bet we weren't more than
5 miles from you.

I guess I should check the group more regularly.

If you see a really nice '80 blue/white top/white stripe Scout running
around town, that's my old one. I wouldn't try to out run it if I were you
unless you're packing some serious heat, for certain don't try to outpull it
since it has a moderately built 392 fuel injected truck motor in it.

John Stricker

Post by Hank
Yes I replaced all the brake pads and bleed them all off as the front
driver side was really grabbing it better now, air filter is really
clean I will continue to check out the other items. My guess is as it
consistant at 17 mpg all is pretty good my understanding is they realy
were not mpg cars and I really dont care as I love to drive it. My
only concern is if its really under par maybe something is wrong with
it. I dont know if the chip is aftermaker as I said I just got the
car. I have a parts car a 96 maybe I will pull the ECM from it and see
if there is a difference its a 6 with a 4 speed also. I cannot believe
the power difference between the 4 and 6 cyl and I am still having
trouble using te 4 speed vs the 5 speed. I am thinking maybe next
summer finding a 5 speed or even swaping between the 2 cars. My
location is Manchester NH.
My 96 Jag XJ6 I ran it down this summer to L.I. NY it got 25 mpg
highway it usually gets around 17 city.
My web site with my cars
http://mysite.verizon.net/vzeecixb/
Hank

Post by JStricker
Last thing first.
For an '85 V6 4 spd that you don't do much highway driving, I'd say you're
doing about average or just a little below, but not much. I don't know of
many V6 4 spd's that will get over 20 in city driving, just not going to
happen.
I'd say that your 4 cyl. with the 5 spd is a little tired. It would
probably do it some good to clean the injector in the TB and also be sure
you set the timing since it's going to have a distributor.
Back to your '85, since you asked how to improve things, I'd start with
double checking everything. If you have access to a good scanner then plug
that in and see what it's showing. Make sure your temp sensor to the ECM is
reading close to what your gauge is reading. Also make sure that your
Intake Air Temp sensor is showing something close to the outside temp. If
these are off, the mixture is off by quite a bit until the ECM goes into
closed loop.
The EGR on these is also prone to some problems particularly getting
carboned up. This problem will NOT set a code. There is nothing there to
tell it that the EGR is leaking or not opening physically. The code is set
by a switch in the EGR solenoid and just because it's sending a vacuum
signal (or not) does not mean the valve is opening (or closing). These are
pretty easy to take off and clean/replace but be careful to not break your
EGR tube, they're like gold to go back to stock.
Naturally, check EVERYTHING. Make sure your brakes aren't dragging, it's a
lot more common than you think. I'd up the air in the tires for city
driving at least 2-3 pounds over what the sticker calls for. Air Filter
clean? Fuel filter clean? I've had good luck cleaning the injectors but I
built my own cleaning tool. A shop can do it on the car and clean the fuel
system very well. Make sure the timing is properly set on the car. If you
have an aftermarket chip ("performance") take it out and put the stock one
back in. For the stock motor, it's a very good chip.
With all that in mind, around town driving kills mileage on a stick shift
car, it really does. There's not much you're going to do to get your
mileage with the 4 spd above 24-25 even on the highway at moderate speeds,
it's just not geared for mileage. You can make sure that EVERYTHING is
right, though, and get everything you can out of it.
If the car were closer, I'd be happy to stick it on my wide band O2 and Snap
On MT2500 Scanner on it so we could go for a drive to see what was going on.
John Stricker
Stock 2.8 and auto
3.4 crate motor and auto
4.9L caddy with caddy auto
383 small block Chevy with 5 speed
4 cyl with 4 spd
4 cyl with auto
6 cylinder with 5 speed
3.4 race motor with Isuzu 5 speed from a 4 cylinder

Post by Hank
My 85 2m4 5 speed 170K miles was getting around 22 mpg I do not do
much hiway driving and its no longer my daily drive.
My new daily drive a 85 GT 6 cyl 4 speed 63K miles still only averages
17 mpg. So how would you go about improving that ?
When I got that car 8 weeks ago I replaced the plugs, cap, rotor, oil
change and gear box oil change and recently replaced the AIC as it was
stalling that stoped. My tire pressure is good there are no error
codes. I even tried for a week to be less lead footed but no change in
mpg.
Hank

[Hank]

Your right yur were less then 5 miles from my house being over by the
arport and I work in Bedford. I'll keep an eye open for the scout. I
have noticed driving along at like 35 or 40 mph 1500 to 2000 rpm 3 rd
gear it is a bit jerky I am still getting in tune with this engine. My
2m4 I could alays tell if the sligest thing was actiing up and could
get it back to normal but I am not as familar yet with the 6 cyl. Any
idea as to why it is jerky like that ?
Thanks
Hank

Post by JStricker
Hank,
You know, this sucks.
I just got around to checking the group and read your reply. Then I checked
out your webpage. You live in Manchester. My wife and I just got back from
delivering my '80 IHC Scout to it's new owner in Bedford on Tirrell Road.
We stayed at the Courtyard over by the airport. I bet we weren't more than
5 miles from you.
I guess I should check the group more regularly.
If you see a really nice '80 blue/white top/white stripe Scout running
around town, that's my old one. I wouldn't try to out run it if I were you
unless you're packing some serious heat, for certain don't try to outpull it
since it has a moderately built 392 fuel injected truck motor in it.
John Stricker

Post by Hank
Yes I replaced all the brake pads and bleed them all off as the front
driver side was really grabbing it better now, air filter is really
clean I will continue to check out the other items. My guess is as it
consistant at 17 mpg all is pretty good my understanding is they realy
were not mpg cars and I really dont care as I love to drive it. My
only concern is if its really under par maybe something is wrong with
it. I dont know if the chip is aftermaker as I said I just got the
car. I have a parts car a 96 maybe I will pull the ECM from it and see
if there is a difference its a 6 with a 4 speed also. I cannot believe
the power difference between the 4 and 6 cyl and I am still having
trouble using te 4 speed vs the 5 speed. I am thinking maybe next
summer finding a 5 speed or even swaping between the 2 cars. My
location is Manchester NH.
My 96 Jag XJ6 I ran it down this summer to L.I. NY it got 25 mpg
highway it usually gets around 17 city.
My web site with my cars
http://mysite.verizon.net/vzeecixb/
Hank

Post by JStricker
Last thing first.
For an '85 V6 4 spd that you don't do much highway driving, I'd say you're
doing about average or just a little below, but not much. I don't know of
many V6 4 spd's that will get over 20 in city driving, just not going to
happen.
I'd say that your 4 cyl. with the 5 spd is a little tired. It would
probably do it some good to clean the injector in the TB and also be sure
you set the timing since it's going to have a distributor.
Back to your '85, since you asked how to improve things, I'd start with
double checking everything. If you have access to a good scanner then plug
that in and see what it's showing. Make sure your temp sensor to the ECM is
reading close to what your gauge is reading. Also make sure that your
Intake Air Temp sensor is showing something close to the outside temp. If
these are off, the mixture is off by quite a bit until the ECM goes into
closed loop.
The EGR on these is also prone to some problems particularly getting
carboned up. This problem will NOT set a code. There is nothing there to
tell it that the EGR is leaking or not opening physically. The code is set
by a switch in the EGR solenoid and just because it's sending a vacuum
signal (or not) does not mean the valve is opening (or closing). These are
pretty easy to take off and clean/replace but be careful to not break your
EGR tube, they're like gold to go back to stock.
Naturally, check EVERYTHING. Make sure your brakes aren't dragging, it's a
lot more common than you think. I'd up the air in the tires for city
driving at least 2-3 pounds over what the sticker calls for. Air Filter
clean? Fuel filter clean? I've had good luck cleaning the injectors but I
built my own cleaning tool. A shop can do it on the car and clean the fuel
system very well. Make sure the timing is properly set on the car. If you
have an aftermarket chip ("performance") take it out and put the stock one
back in. For the stock motor, it's a very good chip.
With all that in mind, around town driving kills mileage on a stick shift
car, it really does. There's not much you're going to do to get your
mileage with the 4 spd above 24-25 even on the highway at moderate speeds,
it's just not geared for mileage. You can make sure that EVERYTHING is
right, though, and get everything you can out of it.
If the car were closer, I'd be happy to stick it on my wide band O2 and Snap
On MT2500 Scanner on it so we could go for a drive to see what was going on.
John Stricker
Stock 2.8 and auto
3.4 crate motor and auto
4.9L caddy with caddy auto
383 small block Chevy with 5 speed
4 cyl with 4 spd
4 cyl with auto
6 cylinder with 5 speed
3.4 race motor with Isuzu 5 speed from a 4 cylinder

Post by Hank
My 85 2m4 5 speed 170K miles was getting around 22 mpg I do not do
much hiway driving and its no longer my daily drive.
My new daily drive a 85 GT 6 cyl 4 speed 63K miles still only averages
17 mpg. So how would you go about improving that ?
When I got that car 8 weeks ago I replaced the plugs, cap, rotor, oil
change and gear box oil change and recently replaced the AIC as it was
stalling that stoped. My tire pressure is good there are no error
codes. I even tried for a week to be less lead footed but no change in
mpg.
Hank

[JStricker]

Hank,

I'd check a couple of things for the jerk, or surge. Vacuum leaks can cause
it if they're small and a bad or plugged EGR valve can do that as well, so
that's where I'd start.

John Stricker

Post by Hank
Your right yur were less then 5 miles from my house being over by the
arport and I work in Bedford. I'll keep an eye open for the scout. I
have noticed driving along at like 35 or 40 mph 1500 to 2000 rpm 3 rd
gear it is a bit jerky I am still getting in tune with this engine. My
2m4 I could alays tell if the sligest thing was actiing up and could
get it back to normal but I am not as familar yet with the 6 cyl. Any
idea as to why it is jerky like that ?
Thanks
Hank

Post by JStricker
Hank,
You know, this sucks.
I just got around to checking the group and read your reply. Then I checked
out your webpage. You live in Manchester. My wife and I just got back from
delivering my '80 IHC Scout to it's new owner in Bedford on Tirrell Road.
We stayed at the Courtyard over by the airport. I bet we weren't more than
5 miles from you.
I guess I should check the group more regularly.
If you see a really nice '80 blue/white top/white stripe Scout running
around town, that's my old one. I wouldn't try to out run it if I were you
unless you're packing some serious heat, for certain don't try to outpull it
since it has a moderately built 392 fuel injected truck motor in it.
John Stricker

Post by Hank
Yes I replaced all the brake pads and bleed them all off as the front
driver side was really grabbing it better now, air filter is really
clean I will continue to check out the other items. My guess is as it
consistant at 17 mpg all is pretty good my understanding is they realy
were not mpg cars and I really dont care as I love to drive it. My
only concern is if its really under par maybe something is wrong with
it. I dont know if the chip is aftermaker as I said I just got the
car. I have a parts car a 96 maybe I will pull the ECM from it and see
if there is a difference its a 6 with a 4 speed also. I cannot believe
the power difference between the 4 and 6 cyl and I am still having
trouble using te 4 speed vs the 5 speed. I am thinking maybe next
summer finding a 5 speed or even swaping between the 2 cars. My
location is Manchester NH.
My 96 Jag XJ6 I ran it down this summer to L.I. NY it got 25 mpg
highway it usually gets around 17 city.
My web site with my cars
http://mysite.verizon.net/vzeecixb/
Hank

Post by JStricker
Last thing first.
For an '85 V6 4 spd that you don't do much highway driving, I'd say you're
doing about average or just a little below, but not much. I don't know of
many V6 4 spd's that will get over 20 in city driving, just not going to
happen.
I'd say that your 4 cyl. with the 5 spd is a little tired. It would
probably do it some good to clean the injector in the TB and also be sure
you set the timing since it's going to have a distributor.
Back to your '85, since you asked how to improve things, I'd start with
double checking everything. If you have access to a good scanner then plug
that in and see what it's showing. Make sure your temp sensor to the
ECM
is
reading close to what your gauge is reading. Also make sure that your
Intake Air Temp sensor is showing something close to the outside temp.
If
these are off, the mixture is off by quite a bit until the ECM goes into
closed loop.
The EGR on these is also prone to some problems particularly getting
carboned up. This problem will NOT set a code. There is nothing there to
tell it that the EGR is leaking or not opening physically. The code is set
by a switch in the EGR solenoid and just because it's sending a vacuum
signal (or not) does not mean the valve is opening (or closing). These are
pretty easy to take off and clean/replace but be careful to not break your
EGR tube, they're like gold to go back to stock.
Naturally, check EVERYTHING. Make sure your brakes aren't dragging,
it's
a
lot more common than you think. I'd up the air in the tires for city
driving at least 2-3 pounds over what the sticker calls for. Air Filter
clean? Fuel filter clean? I've had good luck cleaning the injectors
but
I
built my own cleaning tool. A shop can do it on the car and clean the fuel
system very well. Make sure the timing is properly set on the car. If you
have an aftermarket chip ("performance") take it out and put the stock one
back in. For the stock motor, it's a very good chip.
With all that in mind, around town driving kills mileage on a stick shift
car, it really does. There's not much you're going to do to get your
mileage with the 4 spd above 24-25 even on the highway at moderate speeds,
it's just not geared for mileage. You can make sure that EVERYTHING is
right, though, and get everything you can out of it.
If the car were closer, I'd be happy to stick it on my wide band O2 and Snap
On MT2500 Scanner on it so we could go for a drive to see what was going on.
John Stricker
Stock 2.8 and auto
3.4 crate motor and auto
4.9L caddy with caddy auto
383 small block Chevy with 5 speed
4 cyl with 4 spd
4 cyl with auto
6 cylinder with 5 speed
3.4 race motor with Isuzu 5 speed from a 4 cylinder

Post by Hank
My 85 2m4 5 speed 170K miles was getting around 22 mpg I do not do
much hiway driving and its no longer my daily drive.
My new daily drive a 85 GT 6 cyl 4 speed 63K miles still only averages
17 mpg. So how would you go about improving that ?
When I got that car 8 weeks ago I replaced the plugs, cap, rotor, oil
change and gear box oil change and recently replaced the AIC as it was
stalling that stoped. My tire pressure is good there are no error
codes. I even tried for a week to be less lead footed but no change in
mpg.
Hank

[Hank]

My 2m4 was getting average highway/city about 22 at 180K miles but the
85 GT 4 speed 63K miles I got about 2 months ago is averaging 17 miles
per gallon. So whats up with that, besides my lead foot. O yes all I
use is high test.
Hank

Post by John Craker
The ultimate mileage fiero has got to be an 87/88 4cyl 5spd (not auto!!!!).
I pulled a bit over 40mpg on a highway run.
City was worse of course, but still not as bad as say an '86 GT with an auto
and A/C (about the worst combo... hehe)

Post by PePe_LePu_For2
Mike,
I can't comment on the 4 cylinder mileage because its been 20 years
since I've owned one, but I can tell you what I've been able to get with my
88 GTs. My current car has done 32 on the freeway at least twice so far.
Back when I had my first 88 GT the speed limit was still 55 MPH. Under those
conditions I was able to squeeze 34 out of it once. The conditions of these
mileage records were... Filling up at a gas station near a freeway on ramp,
smoothly gliding out onto the freeway, slowly ramping up to 55/65 in the far
right hand lane, and finally setting the cruise control to the posted limit.
Then I would just take it easy until it was time to refill the tank.
In regular daily commute/city driving you find yourself struggling to
get as little as 28 MPG with a V6. I mostly get around 24 - 26.
Martin

Post by Mike
What kind of MPG can I expect from a Fiero?
Are the 4 cyl any better than the 6?

[labtech1]

depends

I had a 4 cyl automatic that got much worse milage than my V6 standard 5
speed. How ever I guess Fiero made a 'milage maker' car, 4 cyl that did
pretty well.

MPG is suppose to be higher in standard transmissions, and the port
injection is more efficient than the throttle body FI.

Even tho the engine is slightly bigger, the V6, standard transmission cars
seem to run circles around the 4 cyl ones.

Post by Mike
What kind of MPG can I expect from a Fiero?
Are the 4 cyl any better than the 6?

[dave349]

couldn't help but notice this thread but the gas mileage on fieros
seems to be pretty low. i know that standards are better than autos on
gas, so which is better on gas 4 cyl standard or 6 cyl standard. i
always thought these cars woudl get better milage than what you've been
saying because they're such small cars and they have fairly low
horsepower, especially the 4 cyl

Post by labtech1
depends
I had a 4 cyl automatic that got much worse milage than my V6 standard 5
speed. How ever I guess Fiero made a 'milage maker' car, 4 cyl that did
pretty well.
MPG is suppose to be higher in standard transmissions, and the port
injection is more efficient than the throttle body FI.
Even tho the engine is slightly bigger, the V6, standard transmission cars
seem to run circles around the 4 cyl ones.

Post by Mike
What kind of MPG can I expect from a Fiero?
Are the 4 cyl any better than the 6?

[labtech1]

Seems to me my 85 2M4 automatic got about 22 mpg
average. The 88GT V6 standard gets about 30 mpg with highway milage
reaching about 36 mpg

Post by dave349
couldn't help but notice this thread but the gas mileage on fieros
seems to be pretty low. i know that standards are better than autos on
gas, so which is better on gas 4 cyl standard or 6 cyl standard. i
always thought these cars woudl get better milage than what you've been
saying because they're such small cars and they have fairly low
horsepower, especially the 4 cyl

Post by labtech1
depends
I had a 4 cyl automatic that got much worse milage than my V6

standard 5

Post by dave349

Post by labtech1
speed. How ever I guess Fiero made a 'milage maker' car, 4 cyl that did
pretty well.
MPG is suppose to be higher in standard transmissions, and the port
injection is more efficient than the throttle body FI.
Even tho the engine is slightly bigger, the V6, standard transmission

cars

Post by dave349

Post by labtech1
seem to run circles around the 4 cyl ones.

Post by Mike
What kind of MPG can I expect from a Fiero?
Are the 4 cyl any better than the 6?

[dave349]

ok so there's not much point in getting the 4 cyl if i were thinking
it'd be better on gas.

Post by labtech1
Seems to me my 85 2M4 automatic got about 22 mpg
average. The 88GT V6 standard gets about 30 mpg with highway milage
reaching about 36 mpg

Post by dave349
couldn't help but notice this thread but the gas mileage on fieros
seems to be pretty low. i know that standards are better than autos on
gas, so which is better on gas 4 cyl standard or 6 cyl standard. i
always thought these cars woudl get better milage than what you've been
saying because they're such small cars and they have fairly low
horsepower, especially the 4 cyl

Post by labtech1
depends
I had a 4 cyl automatic that got much worse milage than my V6

standard 5

Post by dave349

Post by labtech1
speed. How ever I guess Fiero made a 'milage maker' car, 4 cyl that

did

Post by dave349

Post by labtech1
pretty well.
MPG is suppose to be higher in standard transmissions, and the port
injection is more efficient than the throttle body FI.
Even tho the engine is slightly bigger, the V6, standard transmission

cars

Post by dave349

Post by labtech1
seem to run circles around the 4 cyl ones.

Post by Mike
What kind of MPG can I expect from a Fiero?
Are the 4 cyl any better than the 6?

[Brian]

I've gotten 28/30 MPG consistiently with my 88GT manual 5 spd and have owned
it since 89. Regular tuneups, tire pressure (very important) ,and keeping on
top of the problems should give you fairly similar results. I don't remember
what the 4 cyl was getting (sold in 89) but I don't think it was that good.
If you have a leadfoot then expect far worse MPG

[c***@mts.net]

On Sat, 7 Oct 2006 20:42:01 -0500, "Brian"

Post by Brian
I've gotten 28/30 MPG consistiently with my 88GT manual 5 spd and have owned
it since 89. Regular tuneups, tire pressure (very important) ,and keeping on
top of the problems should give you fairly similar results. I don't remember
what the 4 cyl was getting (sold in 89) but I don't think it was that good.
If you have a leadfoot then expect far worse MPG

On long highway trips in my 2m4 auto, I was averaging 37mi per
imperial gallon ( US gallon 29.6). I was hoping it would get 40 mi
but that's the best I could get no matter what I did. Headlites up
got less miles. They act like mini sails to catch the wind.

Pete

[Phil Randolph]

MY SC3800 5SP Formula used to get a little over 30 MPG highway but after
I added the cam , did some head work and put on headers, I dropped all
the way down to 29 MPG (again highway)

Post by c***@mts.net
On Sat, 7 Oct 2006 20:42:01 -0500, "Brian"

Post by Brian
I've gotten 28/30 MPG consistiently with my 88GT manual 5 spd and have owned
it since 89. Regular tuneups, tire pressure (very important) ,and keeping on
top of the problems should give you fairly similar results. I don't remember
what the 4 cyl was getting (sold in 89) but I don't think it was that good.
If you have a leadfoot then expect far worse MPG

On long highway trips in my 2m4 auto, I was averaging 37mi per
imperial gallon ( US gallon 29.6). I was hoping it would get 40 mi
but that's the best I could get no matter what I did. Headlites up
got less miles. They act like mini sails to catch the wind.
Pete