BluFBdy

iTrader: (1)

Out of nowhere my gas mileage has taken a dump, i dont know why but i'd like some help figuring it out, 2 days ago i filled up FULL and if i remember our tanks are about 16 gallons correct, now...2 days later i am at half a tank. I've gone to school twice, to work, and out for a drive that was no more that 30 miles round trip. school is only about 5 miles away and work the same, i've been keeping my foot out of it hoping this was it but no luck. I filled up tonight and got about 8 gallons into it so i know my gauge isnt off

If my math is right im getting UNDER 10MPG.......this is insane and impossible to boot. My old carbed 81 silverado did better than this.

What can cause this? anything i can do to help it? new plugs? o2 sensor maybe? Any help is appreciated

In the back of my mind i'm tempted to watch my car tonight...i live literally a quarter mile from the QC mini-mexico and they've been eyein up my car...maybe they're taking my gas at night... jk....there no evidence for that

Any way... tips? hints? Advice?

slow_90firebird

Try a locking gas cap, and see if the milage improoves??

BluFBdy

iTrader: (1)

hahah yeah would my plugs have anyhting to do with it? Odd question but with my timing at 0* anytime i shift into 5th its like theres a spark knock and my engine just shakes, i havent tested it at 6* but if i fix it could that aid my mileage?

slow_90firebird

The more advanced the timing, the more knock you will see. And I doubt your plugs would go bad overnight, but it wouldn't hurt to pull one and check it.

I have a knock problem with mine, and I set my timing back to base. My car knocks when I put load on the motor at low rpm's. A perfect example would be, try to start on a hill in 2nd gear. You will have to let the clutch out enough to keep from rolling backward, but you need to give it more gas to keep it from stalling. Right then, my car will knock like crazy.

It will also knock if I get lazy, and try to climb a hill in 4th gear, when I shoud really go to third. When I roll on the gas pedal, it will start knocking. Ironically though, i have never experienced it at a regular WOT run on the highway, or a launch.

1fastam

iTrader: (1)

your timing should be set at 6*. try putting in some 93 octane($$$$$) gas ill bet you your milage picks up enough to run it all the time , my transam runs like crap on regular gas(cheap) get a locking gas cap people do steel gas( hate to think this is whats happening but?) later jimmy

BluFBdy

iTrader: (1)

ah ghetto lol gas is expensive enough lol anything else i should do? i still havent checked to o2 sensor on this thig since i bought it or the cap and rotor

mxcrazed

I did a cap, rotor, wires, plugs and ignition coil in my 97 4.0L jeep grand Cherokee with 178K on it and drove better and the car calculate 4.4mpg better. Now I'm up to 16.6mpg, my tranny slips a little and i don't know anyone else with a 4.0L that gets that. Driving habits alone make a world of difference, locking cap cant hurt, neither could a tune up

slow_90firebird

No, his timing should be at 0*. It says so right on the emission sticker under the hood. 6 degrees is what people here recommend if you dont mind buying 93 octane gas. I ran 6*, and used 93. The car still knocked like an SOB.

Slipjack

+1 on the locking gas cap idea. $10-$15 is nothing compared to losing half a tank in two days.

TraviZ

iTrader: (2)

TPI's are 6degrees.
says so right on the emission sticker under MY hood.

titan

It may be a stupid question, but have you checked/pulled any codes from the ECM?

BluFBdy

iTrader: (1)

1 My driving habbits have been totally changed since i realized this
2. TBI which is what i have, runs 0* so says the emissions stickers
3. what is a locking gas cap gonna do for my mileage?(the mini mexico thing was a joke)
4. I'm constantly checking my codes and i only get that stupid EGR code like 32 i believe? it dissapears on its own?

mxcrazed

take a single strand of hair wet it and lay it across your fuel door JK

I need to knock back my timing

titan

I think you've found your culprit. I too have the damn code 32, and yea it goes away, but....

The EGR is supposed to open up a little bit when you hit and maintain a cruising speed (around 55) and allow some of your emission gases to re-flow through the engine, along with the clean air being taken in. GM did this because they found it increases gas mileage (apparently quite a bit).

I drive around 40 miles each way to work. If I allow the check engine light to stay on, (I only have the code 32) I will burn about 1/4 of a tank of gas. If I pull over and shut it down for around 3 minutes, and begin again, it will not come back on for the rest of the trip, and I can barely tell that the gas needle has moved. Now this isn't a fix, by any means, but personally, I just can't afford the parts to begin fixing it. The solenoid is around $65 and the EGR itself is just over $100. Might not sound like alot to some, but I just don't have that kind of funds... I'm fortunate enough to be getting near the interstate when it turns on, so I simply stop and get my morning coffee and when I resume my drive, it doesn't return.

There's quite a few threads on here about code 32 and the egr system, showing you how to test and diagnose. Sit back, have a coke, and do some reading on it, and see if you can find your fix.

BluFBdy

iTrader: (1)

yeah but heres the bit** part, i had to buy a delco EGR topass emissions back in august, so i know its good and holding vaccum, im gonna check my solenoid and see if i can score it wholesale or at a discount thru my school cuz as far as the dealership is concerned mines a "donation" to the class thanks for the info, normally when my SES light pops ill just shut it off and keep rollin, after about 10 seconds ill just bump start it and it'll be gone (maybe thats part of the reason i busted my tranny mount >_<)

Travis odell

haha you can get a hose in our tanks pretty easy siphoning gas is how i used to get round in my v8 till i got a j.o.b

slow_90firebird

BluFBdy

iTrader: (1)

well i may have found the solution...well...i DID but i dont know if its the WHOLE solution, whenmy tranny mount busted and i had it on the lift i decided to check my #8 spark plug cuz i was bored (i think thats it i suck with the order) its the one on the rear passenger thats impossible to get to from up top, and when i pulled it out i went to pull it out of the socket, and the damn thing dusted apart! ceramic and metal were barley hanging on, so i think i wasnt getting complete combustion cuz its not runnin as rich now. Hooray for boredom! just to be safe i changed all my other plugs too and now its got the power back and my mileage has gone up....or my gauge is lying to me lol we'll see in a few days im just running it off the mileage and how many gallons i can fit into it when i fill up

five7kid

iTrader: (14)

Yep, sounds like your plugs were stealing your gas. . .

One of the reasons we always ask what condition they're in when people complain about poor mileage or running (I've been kind of preoccupied of late and hadn't gotten to it yet on this thread, don't ya know).

TraviZ

iTrader: (2)

You're a disgrace to Travis' everywhere!

BluFBdy

iTrader: (1)

yeah i dont know why i didnt check that, do you know waht would cause that to happen? just a cheap plug? or is my engine gonna eat plugs regularly?