flashing alternator light 1990 L98

[keywestjack]

My alternator light comes on intermitantly. Seems to happen usually when the car is warm, and usually a change in acceleration will make it stop. The battery is ok, new alternator (happened with the old too), belt is in good shape. Any thoughts? Thanks, Jack

[c4c5specialist]

Hi there,

What kind of alternator and what is the rated output ???

What is your battery size and CC ?? Do you have a battery test results???

Are your battery terminals torqued to 11 ft lbs???

Do you have under drive pulleys on the crankshaft ????

Allthebest, c4c5

[keywestjack]

Powermaster

140amps

Terminals torqued

Duralast Gold 2yrs old and checks out OK


Thanks for your help. Jack

[c4c5specialist]

HI there,

What were your battery test results??

You can check your alternator output by checking voltage at the main cable coming from the back of the alternator.

Allthebest, c4c5

[keywestjack]

Battery voltage is 13.8 although when doing a real time scan (while driving) it would once and a while drop down to 12.7

[c4c5specialist]

Hi there,

Check your voltage at idle from the rear of the alternator.

Also, you should have 12.5 volts minimum at 550CCA minimum testing out of the battery.

But it sounds like you have a bad alternator.

Allthebest, c4c5