1998 Pontiac Grand Am

1998 PONTIAC GRAND AM

147,000 MILES • 6 CYL • FWD • AUTOMATIC

EVO9393

MEMBER
2 POSTS

start up ok 2 minutes later battery light comes on. replaced altenator ,battery and checked the grounds.getting 11.80 on voltage from alt to battery. when running its 7.68,. replaced altenator again ,same problem. thank you , moe

Feb 9, 2008 at 5:23 PM

MASTERTECHTIM

✓ASE Certified Mechanic
4,750 POSTS

moe you need to check the fat red wire at back of alternator for battery voltage, sounds like you might have no power there. check back to us.

Feb 9, 2008 at 5:38 PM

RASMATAZ

✓ASE Certified Mechanic
75,992 POSTS

Those readings are just too low- for the engine management to operate properly-The field ciruit is computer generated-in other words the computer acts as a voltage regulator. See below

Need more help don't hesitate

Feb 9, 2008 at 5:44 PM

EVO9393

MEMBER
2 POSTS

do i replace the computer? this is the closest ive been yet lol

Feb 10, 2008 at 9:44 PM

RASMATAZ

✓ASE Certified Mechanic
75,992 POSTS

This is where I stop-If all checks out -the Alty,Battery, and all connections are cleaned and properly connected/tighten.

The computer is the last place I tell the customer to go-its not cheap-especially if there's a wire problem and you hook up the new computer and get fried in sec or 2. Your shot!

Go to an indepedent shop and have them take a shot at it with their machines_

Feb 11, 2008 at 12:03 AM

Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.