Hi everyone, my GTA just started acting up yesterday and scared the **** out of me. Everything was normal as ever, then I pulled out of a parking lot and as soon as I punched it it just stalled at about 1500 rpm. It would not die but would fall to a slow idle with some backfiring, I would let off the gas and it would idle back up!?! It has done this maybe 4 or 5 times in two days and only lasts maybe a few minutes then back to complete normal. I know it burns oil, and the last two tanks have been mid-grade 89 instead of the usual superior unleaded 91-92 octane. Thats the only changes I can recall, I'm just stunned right now, if it was consistent I can imagine whats going but this is insane. Immediately, I'm thinking stuck valve or bad plugs but it wouldn't just go away, this only seems to happen warmed up (160*) and shortly after engine start, not immediately. Could I have a bad TPS? I not completely knowledgable of the TPI yet but I do know for sure it's not a rotating assembly problem. I've had no SES light in all this. Could a 2 octane drop make that big of difference!?! Thanks for your help and suggestions!

 

lancer5067,
Not sure if this is your problem or not but I was having similar symptoms when my fuel pump started to die. It was right around 88 - 89,000 miles.

Replaced the fuel pump... no problem.

Hope this is helpful.

-Schultzy

 

mass airflow sensor sounds as if its saying byebye-could check maf burn and power relays-its a bitch intermittent like it is, to diagnose with certainty when it goes sour again, ck. it by unplugging it-if the symptoms last long enough to allow you the chance-and see if an improvement is observed-could try doing the old tap test on it also-when its idleing pop the hood and gently tap on the maf-screwdriver handle works good-if your car starts to sputter,miss etc-you can put another checkmark in the column that says replace maf. seeya

 

thanks for the advise, it was on the money! It started happening again, so I unplugged my MAF and just like that it quit and never came back. It really pisses me off since I JUST bought a Wells MAF in January. My car idles like **** but at least it goes above idle! Again, I appreciate the help, I would have never guessed and even scoffed at the idea Thanks!!