Rough running LT1
Thread Starter
Racer
Joined: Oct 1999
Posts: 372
Likes: 1
From: Santa Fe TN
Rough running LT1
Hello again, one more question!
We have a '93 Ruby, LT1 automatic, with 199,000 miles on it, a daily driver. It will occasionally (every few months) suddenly start running very rough, will barely hold idle, and will seeming run very rich, with black smoke coming from the exhaust. It doesn't throw a code. If we disconnect the battery for a few minutes and reconnect, it will start and run perfectly, as if nothing ever happened. It's had it's optispark replaced two years ago, at about 150,000 miles, but it occasionally did this before the opti replacement. Any ideas?
Thanks!
Mark and Jennifer
We have a '93 Ruby, LT1 automatic, with 199,000 miles on it, a daily driver. It will occasionally (every few months) suddenly start running very rough, will barely hold idle, and will seeming run very rich, with black smoke coming from the exhaust. It doesn't throw a code. If we disconnect the battery for a few minutes and reconnect, it will start and run perfectly, as if nothing ever happened. It's had it's optispark replaced two years ago, at about 150,000 miles, but it occasionally did this before the opti replacement. Any ideas?
Thanks!
Mark and Jennifer
Burning Brakes
Joined: Nov 2004
Posts: 781
Likes: 0
Maybe start with oxygen sensors. Once the car warms up and goes into CLOSED loop, it uses the oxygen sensors to trim fuel. When you unhook the battery and 'start over', the car starts back up in OPEN loop and does not initially recognize the oxygen sensors.
Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
Originally Posted by onedef92
Try cleaning your TB and IAC motor, too. Check the C4 Tech Tips section for the how-to info...
