1998 Buick Century Will not stay running

GOSSELSM01

MEMBER
1998 BUICK CENTURY
6 CYL
FWD
AUTOMATIC
181,000 MILES

New Alt. Battery good and tested. Battery connections clean. Car starts and runs foir a bit then stalls. If I turn on the lights, rear window defroster, turn signals, the engine stops. I have 5 volts at a 3 wire sensor under the hood. !4 volts when engine is running and 11.6 with engine off. Ignition mod good and tested, coils good. I checked for voltage drop in fuse box. Car stalls when ever I turn on lights or the such and with engine off I have voltage drop. I checked the row D of the interior fuse panel.

Help

1 Reply

ERNEST CLARK

MECHANIC
1,730 POSTS

Your issue is definitely a complicated one. When engine electrical issues like yours occurs (After checking everything you already have), that usually makes a mechanic suspect a bad computer.

However, you didn't mention anything about checking your ground. There'll be an engine strap connecting the block of your engine to the frame of the car. And then of course from your batter either to the engine block or the frame. Check to see if any of the terminations are loose or corroded.

Then, check all connections at the engine's wiring harness and at the computer. One or more of these connectors could be loose/corroded.

Combined with these checks and the ones you've performed already, I'd say your computer is shot.

I may be missing something, so maybe another technician on this forum has something to add.