O.k. I pulled the negative terminal on the battery for 30 mins and then started it up and let it idle for a couple minutes. Aftwer doing this, I went for a spin for about seven miles. In that seven miles, my gas gauge dropped a whole eight of a tank. So, I think my mileage has gone down even more now. (i can't fully judge this as I took it down the street and on the road for like 10 mins) I have no CEL or anything like that. I don't know whats going on at all. Please help me.

 

anyone? lol

 

Have you tested the IAC yet? lol

 

8th of a tank? is the tank full? it could be that the fuel level float get jacked up? spark plugs? do you notice any sort of hesitation or difference in how the car drives?

 

^+1, also the fuel gauge (on any car) is not the most accurate way of determining fuel consumption. It is highly dampened, electronically in our cars, to prevent it from flailing about as the fuel sloshes around; that's why it can often rise or fall even if you have only driven 10 feet.

Fill the tank and reset the trip odometer, then drive until you have used at least 1/2 tank. Fill up again and note how many gallons it took, and how many miles you traveled--then do the math, that will be your true mpg.

 

I still have not done the IAC thing that cliff was talking about. However, since I have no CEL, is it still a possibility that my spark plugs or 02 sensors are bad and causing my bad gas mileage? How about the MAF or throttle body needing a cleaning?

 

Check the IAC, if it were running crazy rich you'd have DTC.

If the MAF were "dirty" it would be running lean (the MAF would be reporting less air flow than actual), the TB would have to be plugged up tight as a pig's back end to create any issue in normal driving.

A sticking or stuck, or even open/shorted, IAC will not throw a code as there is no feedback from the IAC to the PCM.

It could be a failing, but not yet failed, front O2 sensor--however to actually be burning as much fuel as you feel it is the engine would have to be running pig-rich (same pig) and a short term fuel trim code would be thrown...

 

Cliffy, I pulled the bigger IAC valve that comes from the air intake tube with the black platic box thing around it and the car just completely shut off. After that, I put it back and then started ti back up and pulled the smaller valve and the engine started to drop in rpms and basically hesitated to stay alive. I then turned the car off. What should I do now?

 

Huh? There is only one IAC valve, it's on the front side of the upper plenum, and I meant that you unplug the electrical connector with the engine warm and idling--not disconnect any hoses...

 

Woops. What do you mean my electrical connector?