Engine Performance problem
1990 Chevy Lumina 6 cyl Front Wheel Drive Automatic 1.6K miles
1990 Chevy Lumina, 3.1 V6, auto trans. NO CODES display. Vaccum test gauge reads "retarted timeing" at idle. I cannot find a vacume leak. Car hesitates when fuel pedel is first pushed, then accelerates fine. I changed throttle position sensor, no change. I unplugged the Knock sensor, makes no change in reading on vaccum gauge and sets no chk eng code while unplugged. I was originally checking vaccum to transmition modulator valve for cold 1st to 2ond shift problem. Timming chane??? Bad computer or connection???
1990 Chevy Lumina 6 cyl Front Wheel Drive Automatic 1.6K miles
1990 Chevy Lumina, 3.1 V6, auto trans. NO CODES display. Vaccum test gauge reads "retarted timeing" at idle. I cannot find a vacume leak. Car hesitates when fuel pedel is first pushed, then accelerates fine. I changed throttle position sensor, no change. I unplugged the Knock sensor, makes no change in reading on vaccum gauge and sets no chk eng code while unplugged. I was originally checking vaccum to transmition modulator valve for cold 1st to 2ond shift problem. Timming chane??? Bad computer or connection???
Sep 21, 2008 at 5:23 AM
