97 Protege LX - check engine light

[reyno21]

Hi,
I just bought a 1997 Protege LX just over a week ago. First it was stalling and idling badly, so I put some fuel cleaner in the gas tank and filled it up with premium fuel. That really helped. The car sat for a year so there was probably water in the tank from condensation. Anyways, then there was this noise that came whenever the car moved forward, on or off, and was really loud when you went slow. Turned out to be the backing plate was all rusted and rubbing on the rotors??, I think. They removed that and sound is all gone. Now the check engine light came on Friday, so Sat. morning I took it to Coast Tire and they put it on the computer and said it came up with an emissions code. The code was PO455, Evaporative emissions control system leak detected. They suggested replacing the gas cap because it didn't feel right. Maybe the seal wasn't good. Soon I will have to replace the filler neck, too, as it is getting pretty bad. Okay, I thought, I'll check into that on Monday. Well, over the weekend, the car has stalled a few times and doesn't always idle properly. Do you think the emissions problem and the stalling, etc. are related? No offense to knowledgeable ladies out there, but I'm a girl who doesn't know alot about mechanical stuff. Any suggestions?

[Doug Tatham]

They could be related. I haven't run into it myself before, but I can see how it could happen.

[growe58]

Probably checking in too late to matter, but I doubt the two are connected.

The evaporative emmissions control circuit captures the evaporating vapors from the gas tank while the car is parked and sucks them into the engine to be burned the next time the car is running. Better for the enviornment than allowing the gasoline vapors to evaporate directly in our breathing air. Usually doesn't have much affect on how your car runs whether it is working or not, although it can cause some problems.

The Proteges are famous for bad Idle Air Control (IAC) devices. If the car is only causing problems at idle, runs well and delivers good mpg the rest of the time, I would bet that was your problem. Basically the engine uses so little air at idle, that the throttle plate isn't sensitive enough to insure a clean burn for emissions. So the computer bleeds the correct amount of air in through the IAC. If it isn't working, you will have idling problems. Sometimes, it's only the air passages that are clogged and if you remove the throttle body and clean everything out, you can get it working again.