91 L98 won't idle
Thread Starter
Le Mans Master
Joined: Jul 2001
Posts: 5,297
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From: Stamford VT
91 L98 won't idle
Over the winter the car started and ran beautifully every time I started it. Then suddenly, one time it suddenly stalled and I couldn't get it to start. Pressing on the accelerator allowed me to start it, but as soon as I took my foot off the gas, it would stall. It also threw an "oxygen sensor rich" code.
Scan tool doesn't reveal anything out of the ordinary. Map sensor, tps, temp sensors, etc all function properly.
I plugged the vacuum line that goes to the purge cannister and this seemed to help a lot. Now the car can start without throttle input, and will almost idle on it's own. It takes a lot less throttle to get it to idle now, but it will still stall when I pull my foot off the gas. RPMs don't wander like it's looking for an idle or has a vacuum leak. Last night I swapped in a spare IAC and it made no difference. I took the car for a ride the other night, and it seems to drive ok except that the rpms dive when I throw in the clutch, and when I accelerate it seems to be a bit hesitant at first.
I'm out of ideas. What the hell do I check next?
Scan tool doesn't reveal anything out of the ordinary. Map sensor, tps, temp sensors, etc all function properly.
I plugged the vacuum line that goes to the purge cannister and this seemed to help a lot. Now the car can start without throttle input, and will almost idle on it's own. It takes a lot less throttle to get it to idle now, but it will still stall when I pull my foot off the gas. RPMs don't wander like it's looking for an idle or has a vacuum leak. Last night I swapped in a spare IAC and it made no difference. I took the car for a ride the other night, and it seems to drive ok except that the rpms dive when I throw in the clutch, and when I accelerate it seems to be a bit hesitant at first.
I'm out of ideas. What the hell do I check next?
Thread Starter
Le Mans Master
Joined: Jul 2001
Posts: 5,297
Likes: 0
From: Stamford VT
Fuel pressure is right where it belongs. I hadn't thought about a stuck injector. I was having problems with one not firing, but I never thought about one being stuck open. I don't really have a fuel smell nor a "rich" code now that I unplugged the evap cannister though.
I've got a set of injectors around. Maybe I should try swapping them in.
I've got a set of injectors around. Maybe I should try swapping them in.
