1996 GMC C2500 Setting the timimg

FORCHARD

MEMBER
1996 GMC C2500

Engine Performance problem
1996 GMC C2500 V8 Four Wheel Drive Automatic 300000 kilometers

I just had my 350 vortex rebuilt, we just installed it and it starts, just want to check the time to see if it what it should be, some say I need to do a computor scan? Can it be done with a timing light and whats the process.
tks frank

1 Reply

PEAR69

MECHANIC
1,482 POSTS

You cannot use a timing light to set the timing on these engines. You can get it close but, the computer advances and retards the timing automaticaly- for this reason you need a scan tool capable of doing the timing proceedure. This usually means a trip to a dealer or a GM tech mechanic with a GM TECH 1 or 2 scan tool and software. The old days of timing your engine with a timing light are gone.

BTW - this proceedure is not easy - even with a scan tool. The setting must be within 1 degree at operating temperature. Also, the transmission is very sensitive to engine timing.