Gas Mileage

[nascar24jd]

First let me start by saying, I really like this car. Lots of power, never misses a beat. 1993 Firebird, 3.4L, 139,000 miles. I am just wondering about my gas mileage. I am getting about 16mpg local driving, and about 18-19 highway driving. Does this seem low to you? It seems low to me, but like I said earlier, I really like the car and I am not willing to sink tons of cash into it, so it is what it is. I am just looking for opinions. Thanks.

[Tradition_F]

Re: Gas Mileage

maybe try seafoaming your car, i heard that can improve gas mileage a bit ;)

[Cyborg]

Re: Gas Mileage

Well, I usually get about 19 MPG town driving, and, I made a 300 KM trip (total 350 after getting around in the city) and I filled up this evning, came home, and recorded a result that made my jaw drop. If my calculations are right, I was getting 28 MPG (and I do have a quite heavy foot, especially while on the highway)

This is in my 94 3.4

[nascar24jd]

Re: Gas Mileage

That's what I thought. One clue that I have is that my car has no Cat. Also, I think it is supposed to have an oxygen sensor after the Cat, and I do not have one. The computer might be telling it to run rich due to that.

[notsonic]

Re: Gas Mileage

nope no o2 after the cat. just in the manifolds.


i get around 17-19mpg depending how erm "spirited" i drive. (which is typically all the time.)

i did tons of crap to try to get it higher. new plugs, wires, coils, o2s, oil change, fuel filter, air filter.

it basically stayed the same.:mad:

95 3.4l auto

[nascar24jd]

Re: Gas Mileage

nope no o2 after the cat. just in the manifolds.


i get around 17-19mpg depending how erm "spirited" i drive. (which is typically all the time.)

i did tons of crap to try to get it higher. new plugs, wires, coils, o2s, oil change, fuel filter, air filter.

it basically stayed the same.:mad:

95 3.4l auto

Thanks for the clarification. I might try a few things to see if it will improve. I don't think it is plug / wire related because the car runs so well. My guess is something in the ecm, but i'm not sure.

[BobbyZ72]

Re: Gas Mileage

my 97 3.8 was always getting 26 hwy, and thats with no egr and 180 tstat

[RadRacer]

Re: Gas Mileage

My 97 3.8 gets about 30 highway, and 22-23ish city. That's with a Moroso intake, a MagnaFlow Cat-back system, and a gutted cat. Still haven't bought my O2 sim, so I'm getting the SES light, but I highly doubt that's making me get better mileage. Car only has ~75k miles on it, and I drive it like I'm racing. I merge onto the interstate at ~90MPH :banana:

As for yours, I'd definitely seafoam it. Coming onto 140K, and I bet it's never had the injectors cleaned or anything. Buy 2 cans of seafoam and 1 can of SeaFoam creep from your local auto parts dealer, and then follow the instructions on this page:

http://ls1tech.com/forums/showthread.php?t=534376


Once your done with that, it should get better mileage since it cleaned all that crap out of your engine. If it stills not up there, try new plugs and wires, maybe even coils.


BTW- Your name, nascar24jd, what's the jd stand for? Was it supposed to be jg? I like nascar too, and my fav driver is #24, Jeff Gordon:banana: :banana:

[nascar24jd]

Re: Gas Mileage

BTW- Your name, nascar24jd, what's the jd stand for? Was it supposed to be jg? I like nascar too, and my fav driver is #24, Jeff Gordon:banana: :banana:

Yes, my favorite Nascar driver is Jeff Gordon. JD is my initials. Too bad that the championship hopes for this year do not look good as of late.

[3.4 slow to go]

Re: Gas Mileage

I just fillled up the other day, and got around 25mpg mixed driving. 94 3.4 5sp, approx 132k miles

[Metallibird_Y87]

Re: Gas Mileage

Grand Rapids to chicago...33mp:excited:g
2002 3.8 Y87 auto
I just got the car and did a mileage run
I obeyed all speed limits, even the 55mph crap in indiana.

[97rs4life]

Re: Gas Mileage

Grand Rapids to chicago...33mp:excited:g
2002 3.8 Y87 auto
I just got the car and did a mileage run
I obeyed all speed limits, even the 55mph crap in indiana.

Hey man you from GR? If you are that is sweet cuz I am too! If you are from GR, check out mifbody.com it is a great site for us michigan peeps to hang out on and meet others in the area

[Fbody3400]

Re: Gas Mileage

That's what I thought. One clue that I have is that my car has no Cat. Also, I think it is supposed to have an oxygen sensor after the Cat, and I do not have one. The computer might be telling it to run rich due to that.

My former 3.4 has no cat and was averaging 28 mpg with the AC on a few weeks ago. Clueless good mpg FTW!!1!1eleven!!1!

[bradmb]

Re: Gas Mileage

18-19 in the city. 24-26 on the highway. 1993 3.4 a4

[nascar24jd]

Re: Gas Mileage

I filled up today, mix of local and highway driving, average was 19mpg. Not horrible, but not great either. I only fill up about once a week, so it is really not that bad.