So to start off with I'm getting 120miles per tank if I'm lucky, just did 107miles on 12gals of gas. Plugs, wires, cap, rotor, msd coil, fuel filter all replaced in the last year. Car runs smooth, idles smooth, doesn't seem like anything's wrong except for the horrid gas milage. I was told by my father law that you can check your timing chain by taking the cap off, putting a wrench on the crank pully bolt and then seeing if there's any lag between turning the crank and the rotor turning. This sound about right? If so then the timing chain should be all set....unless it doesn't account for stretching. Got a CAI as well which on my escort bumped me up 2mpg. Any ideas? How hard is it to take the fuel injectors out your first time? I'm getting a very low milage 3.4l next month, thinking about taking the injectors off of that and putting them in.

 

leaking gas tank maybe? or maybe check your vapor canister

 

Timing chain bit is correct. As well as you need to throw a timing light on and check that.

Some cai help milage, some dont. Being a bird, you have a crappy intake and will prob benifit.

Installing the 3.4 injectors on your 3.1 will be WAY to much causing even worse milage.

On your tuneup, you totally forgot the o2 which is the key thing for milage. Also check your wheel bearings, tire pressure, alignment, radiator, trans fluid, rear axle fluid, and how your driving the car. All that factors in.

 

Tranny fluid and rear axle oil really are a factor with mileage?

 

don't forget to check for a stuck open thermostat!!!

 

O2 is 2 yrs old, tire inflation is good, just checked all the tires since the car sat for 6 months with a broken brake booster. Tranny fluid is less then a year old. I'll have to check the rear end again, I know the fluid was topped off a few years ago, haven't checked it for a while though cause I got a 4th gen rear waiting to go in. Stuck open thermostat I would think would make it so the car wouldn't heat up in this 10degree weather which it does fine and just like it always has. There is a hole in the very top of the gas tank but it doesn't leak. Wheel bearings were brand new 3yrs ago, and I repacked them this past summer. Here and there I drive quickly, I'd say like 30% of the time I drive hard and 70% I drive it pretty easy, most I'm going to would be 3k rpms 70% of the time. I let it run for about 20mins before I leave the house or before I leave work so that's not helping any but I do the same with my escort and I'm still getting roughly 30mpg.

Reg ac delco plugs, bosch wires, bosch O2 sensor. Is it true that the diff cover is a checmical or liquid gasket or is there a felpro gasket for it and if so what's the part #...if anyone has it on hand, otherwise I'll find it.

 

Very little, but yes.

Tranny fluid: if its dirty, to thick, low, high, etc. It wont allow it to shift properly. As well as the tranny flings that stuff around and has to work harder to fling it.

Axle: flings it around as well. As well as if its to thick it wont get between the right parts and cause more friction, heat, and pre-mature wear.


Noc. the hole in the gas tank itsnt helping even if its not leaking. It will slowly evaporate. Sitting idle and your drive style sound like its your main factor. However, I understand the sitting idle to warm up.

Try adjusting your drive style and not let it warm up so much and see what happens. When air temp warms up, fix that tank. Also, the colder the air, the more fuel the engine requires, which doesnt help either. It may also be your state requires oxygenated fuel during winter time, which also kills milage.

 

pull that 6 out and get an iron duke.

or fix the hole in your gas tank.

if its got a hole,its leaking.

and check your cat converter and o2 sensor.

changing those two should get you better milage.

i changed my 02 and i got 5 more mpg,i average about 30mpg combined . 25 city,35 hiway.

but i never put in more then $10 becuase cars get there best milage on the LAST few gallons of gas.

and switch to a 5 speed,autos suck the gas.

and try enviromax,its supposed to get 30% better milage with less emmisions.

 

^agree

My mileage went down 3mpg this fall when temps finally dropped.

Even at 10* out, I wouldn't let it warm up more than 5 minutes (and I grew up in the tropics so 50* is too cold to me), it will warm up faster if you drive it from having a load on the engine. Letting it sit and idle really sucks a lot of gas.

 

What the hell is enviromax? Exhaust is new from the manifolds all teh way back. If I get a bolt for the hole and put plumbers tape on it will that hold me until next year when I get around to changing the rear end? Doesn't make sense that warming the car up would be affecting it that badly, again not to beat a dead horse but my escort gt, 29mpg, I warm it up the same and drive it just as hard if not harder...

 

The escort is designed to be an efficent (sp) car. So it sips gas at idle, and not alot running.

The camaro is a "sports car" designed to use gas at idle, and drink it by the gallon under peddle.

Its like comparing potatos to apples.

 

I should swap the escort motor in the friggin firebird, escort has 130hp stock out of a 4cyl.

 

you can put a decent duke in for next to nothing.and you should get 30mpg with no problems.

but you should try enviromax ,its supposed to get 25% better milage.

http://www.storesonline.com/site/onlinegassaver


and if you have a hole in your tank the gas will evaporate throu it,it might not leak,but it WILL get out.

not to mention the vapors could ignite and burn you and your car up.

that would suck.

 

I'm gonna be swapping in a 3.4l in about 7 months, would just be nice if I could make it so I wouldn't go through 450 gallons of gas by then.

 

try the enviromax. it should get you better milage.

 

Def. check the timing. My car seemed fine, my mechanic timed it right and Ive went from 16mpg freeway to 20, mostly citying driving. Check air filters too, my last car was dumping gas for some reason into the motor and my air filter was damn near black. As soon as I replaced that my mileage jumped back.

 

It's got a new K&N cone filter, I'll have to do the timing on it.