johnsonmtz
Newbie
'89 5.7 TBI Reman engine with 35,000 miles and distributor was new when engine installed 4 years ago. I had a suspicion my timing was off a little so I decided to give it a check. With the engine warm and ESC wire disconnected it was almost at 4*. I adjusted back to 0* in base timing, reconnected the ESC and fired up. The engine loped and stumbled for about 10 seconds then found its idle. Immediately the SES light came on. Went for a test drive and all seemed okay and just assumed the SES was because ESC had been disconnected. NOPE!
Pulled in the drive, shut it off, then restarted. Engine loped, bucked, stumbled and misfired badly with any throttle. I've had the Ignition Control Module crap out before so thought maybe it somehow chose this moment to die again. I get a new ICM, install that, and there is some improvement but still lopes and stumbles on start up, finds idle after a few seconds, then SES light comes on. Exhaust smells awful so I think I'm running super rich.
I checked the codes and only get 12, diagnostic mode, and 3, end of read. I'm going to get a different timing light and see if maybe mine is junk and I accidentally set base timing incorrectly. If that's not it, what other things can I check and/or replace?
Pulled in the drive, shut it off, then restarted. Engine loped, bucked, stumbled and misfired badly with any throttle. I've had the Ignition Control Module crap out before so thought maybe it somehow chose this moment to die again. I get a new ICM, install that, and there is some improvement but still lopes and stumbles on start up, finds idle after a few seconds, then SES light comes on. Exhaust smells awful so I think I'm running super rich.
I checked the codes and only get 12, diagnostic mode, and 3, end of read. I'm going to get a different timing light and see if maybe mine is junk and I accidentally set base timing incorrectly. If that's not it, what other things can I check and/or replace?
. My hand had slipped loosening the distributor bolt and I must have knocked it off it’s fitting. I reconnected the tube and bingo, it runs like a champ.
