davbell22602

1990 chevy c2500 with tbi 350 setup but the vortec block/shell.

Can you time an engine with the ses light on? The haynes manual said to fix whats causing the ses light first before timing. I have buddies that timed engines with the ses light. They timed it, then fixed the cause for the ses light, and then re checked the timing.

mudmaniac

You need to disconnect the dist wire under the glove box to set the base timing. This eliminates the computer from the equation.

davbell22602

I dont have one. this is 90 truck not 96.

MDTAHOE

The truck absolutely has a set timing connector either under the glove box or near the fire wall. 1996 does not have one, you must time it using a scan tool.

Speedy650

on the passenger side under the hood, theres a black cover. remove that cover and their is i believe a purple wire with a black stripe on it. it has a disconnect, unhook that, set your timing, then re-connect (i believe after you shut the truck off) and you should be good to go.

dmann13815

don't forget to dissconnect the battery to reset the engine light after your done.

mudmaniac

This is the method you must use on Chevy trucks with TBI from 87 - 95

davbell22602

So its ok to put it in time when the ses light on?

MDTAHOE

It can be done if you have too, as long as the idle speed is not beging affected by the problem causing the CEL.

davbell22602

ok, well right now its too far advanced. Talking about the engine racing bad after running 10-15 seconds.