bad idle problems

hey guys, i usually hang out over in the honda/acura section but my roommate is having a problem with his 91 celica gt-s so i figured i'd come to you.

OK, so as I said this in in regards to a 1991 Toyota Celica GT-S, it is automatic, and has the 2.2 liter engine.

A few weeks ago his alternator went and he took it to a shop and had that fixed. unfortunatly one of the battery terminals was shorting out and it fried the new alternator which the shop fixed free of charge.
Problem is after he got it back from the shop the second time the engine was occasionally idleing funny and when he would put it into reverse it would stall out.
He took it back and they cleaned out his throttle body, and said thats all they could think it was.

Well its been about a month and the idle has been getting gradually worse until now it happens constantly. The idle keeps bouncing from about 1100 down to 400 and back. He also says that he can smell gas vapors around the exhaust pipes?

Just wondering what you guys think it could be, he has an appointment at toyota on friday, so maybe i can figure it out first and save him some money. Any help will be greatly appreciated.


Thanks in advance,
Will

I dont meen to sound like a broken record, but has anyone checked out the vacume lines? there are a lot of hidden ones. one may have been knocked lose when the shop changed the alternator. also may be dirty injectors, try some fuel injector cleaner. good luck!

well i assumed that if it were a vacuum line it would not have started off as a very minor stumble while idleing and through the course of a month gotten to be constant and severe lopeing, if a vacuum line was disconnected wouldn't it just lope from the point it was disconnected till it was reconnected?


Also if it was dirty injectors then it wouldn't be getting enough fuel correct? so then why would he be smelling unburned fuel by the exhaust?


And I apologize I realize this probem has been asked about before, I did do a search and really the only thing that came up was vacuum line, but like I said i didn't think that was the problem but I will check that out tomorrow, in the mean time any other suggestion would be greatly appreciated so that I could check as much as possible tomorrow.

well with the vaccume lines are lose or leeking they can start off like that and in a relitively short time, get worse, depending on how often it was driven. and for the injectors, when they are dirty, they dont inject less fuel, they inject the same ammount, but the fuel comes out in a streem insted of a cloud like it should(make sence?) ya know. but vaccume leeks do things you wouldnt beleve! was the raw fuel vapor coming out of the exuast wile the car was running well or just when the idle was mess'd? it almost sounds like one or more of the cilinders is not fireing. i dont know a whole lot about the newer celicas(mines a '78), so im just throwing you anything i can think of basicly. the only other things i can think of is to check all the realys and make sure the wireing harnes is plugged into each of the injectors, and see that you're geting spark at all the plugs. good luck man, keep us posted

hey thanks for the help, i kinda thought that it may be a cylinder not firing properly also. As for the injectors yeah i see what you mean now (stream vs. spray) but my roommate said that when the problem started he tryed injector cleaner. Anyway hopefully i'll have time to give it a once over tomorrow, and i'll let you guys know what i find. Thanks again.

turns out it was the MAP sensor.

well thats good that you finaly got that taken care of. not having a car is really lame. I'm sorry i couldnt be much help, but at least its fixed now.

Spiffy picture oldbluecelica.... ppl really do that?!?!? neato...