Why my V6 3.1 wastes so so much gas.???? Things i changed, to try to help reduce the gas consumption, and still nothing. 1. All fuel injectors 2. All spark plugs 3. All spark plug wires 4. Ignition module 5. Distributor cap 6. Air filter 7. Fuel filter And my gas tank does not leak. i drive normal a total of 50miles in the city and burn a full tank of gas. That is real crazy it eats more then a v12. Some one can you please help me.

wow. well with that kind of comsumption, does it have any drivability problems?

I don't see checking your timing in there....very important.

O2 sensor. $20 and it's probably time to change it, even if it's not your main problem.

See the thing is, i also changed the o2 sensor like a month ago and the check engine light still stays on i tried disconnecting the battery for 15min so it can reset it self but nothing happened it still comes on and stays on.

see that's just it, it rides fine just when idling it seams to go up and down the rpm but very light.

the car seams fine but its far from it with this type of gas consumption.

See now this is one thing that i did not do.

i am going to talk tomorrow with someone that has a timeing gun

OMG and i thought my 250 miles per tank was bad!


Um well your on the right track of fixing the problem. Honestly though. Everything that has mentioned will help....i think you have a leak somewhere.


THERE is NO way that your car would burn THAT much gas for that many miles. You must have a leak. Double and triple check that you dont have a leak. Do you smell gas at ALL when its sitting or driving or anything. If you smell it while your driving you, for sure, have a leak somewhere. It might not be in the tank but could be in any of the lines even the return line. It could be at the back of the manifold. It could be anywhere.



Also while I thought of it. What injectors did you use to replace the old ones. What brand and what flow rate?

Sure it not leaking from the lines, like the return line.

well when its parked i have the car on/running and see no leaks, but i do smell a lil gas some times when i drive in traffic but very faint.

See what the code is for the check engine light. That could narrow it down quite a bit.

i had this problem to man
both the EGR and O2 went bad
change the egr and O2 then seafoam that bad boy and u should be good

Sounds to me like either a vacuum leak or a MAP sensor problem. More than likely a MAP sensor problem since the light comes back on after the system is reset and not having been run...

Need that code!

:edit: I used to be there... My car was getting that kind of mileage when I first bought it (with the factory 2.8 and all sorts of crap screwed up under the hood). Hated filling it up to go 35 miles to school (using half a tank to get to the cheapest gas station in the area halfway there) and having a quarter tank left when I got home...

Replaced the engine, ECM, most of the sensors and ALL of the fuel injectors and ignition parts, and now I get 400+ per tank when I want to...

milage that bad has to be a leak, i had a leak but the smell wasnt strong.
it ended up being the charcoal canister.
when you undo the petrol/gas cap is there a hissing sound or woosh of air as the tank equalizes with air pressure ??

Well, when I had my 98 V6 Firebird I had a major power loss and I started getting horrible gas mileage. Turned out to just be a collapsed catalytic converter. Just an idea you may want to check out. Also check to see if you have an exhaust leak somewhere (maybe a cracked exhaust manifold?). But still even if you are having those problems I think you'd still be getting better gas mileage. The only thing I can think of that would make for such horrible gas mileage is things that have already been mentioned such as a vacuum hose leak or a fuel line leak. I know you said you changed your filter but did you check to see if your Fuel pump was working correctly?

no

i have all new pipeing

How much do you take at fill up?
Only thing I can think of is dented tank....

First thing I would look for is vacuum leaks. It might not even be the lines. It could very well be a gasket that has dried out and hardened. Touch all the lines. If black rubs off on your hands, they are toast. Check also the PCV elbows on both valve covers. They have been known to crack and leak as well as that big plastic vacuum fitting in the back of the lower intake manifold. Second, if you are smelling gas at idle or right after the car shuts off, your canister purge solenoid may be to blame. If it is stuck open all the time, it will purge constantly. This is a big waste of fuel. Take the canister off and see if it is full of fuel. If it is, its shot. The fuel pressure regulator could also be to blame. Last thing, just a quick question, when you installed your new injectors, did you use new O-rings and did you lube them before putting the injectors in the car? If not, one or two may have chaffed or rolled up causing a vacuum leak at the intake manifold. This will make you rip out every last hair on your head trying to track it down.

i put a new fuel regulator, and my injectors i put them in fine, the reason why i even put the new injectors was because it wasted so much gas.
i had some one do a vacuum leak check on the car for me and they said there is no leak he even double checked.

today im going to check the canister and let you know if thats it.

Thanks.

if its real empty i put about 34$ to fill it up but im always around 28-30 dollars to fill it up

i checked the canister and it had no fuel what so ever in it.

so if fuel is pouring out the bottom of my charcoal canister my purge solenoid is stuck open?

This is usually caused by having the return and vent lines reversed at the gas tank.

RBob.

thanks RBob

no hissing, venting when undoing the cap is a leak.
take the rubber hose from the canister to the metal fuel pipe, tank vent - take it off, block off the metal pipe and use it like that and see what happens, that will tell you if its the canister or not.
sounds like it though

and that hose to the metel fuel pipe "tank vent" should not fill with liquid gasoline correct? Should only be vapors that reach there as far as i'm understanding.
switched my hoses around on the only two that could possibly be incorrect at the tank, one goes to a breather back there another goes to the fuel filter, if one going to fuel filter was wrong then no gasoline would reach my engine i'm guessing.
I had repaird one fuel line, replacing it halfway as other end whent up and around my transmission ( I know believe to the canister) When I was replacing it there was fuel in the line, and a vacuum occurd, wich was no fun as I had to hold the line from gasoline pouring out while i woorked ont he other end of the line. So maybe the same line was going to my canister and this vacuum was causing it to spill out my canister. Gonna drive her and cross my fingers