Charging problem... i think...

[GSP]

Car starts fine and scan master shows 13.8-14.2... untill the car warms up. I talk'n like a good 40mins of driving then the scan master shows 12.8-13.4.. if the headlights, a/c blower, and radio are on and i hit the brake it drops to 11.8.. then bounces up to 12.8-13.2.. advance has checked the alternator on the car and i had an alternator shop check it off the car, it checked ok both times.. is this normal?

 

[GSP]

Was this a dumb question?

 

[phil_jordan]

not a dumb question at all. I seem to be having the same issue. I found that the voltage varies a lot(FOR ME) when my radiator fan comes on. a few of the guys run volt boosters and such to avoid that low of voltage to the injectors and FP. I myself is considering one of those. HTH

 

[Red C5]

Bad grounds? Battery getting weak? They check the regulator and alternator? Maybe you need a higher output alternator?

 

[The Radius Kid]

http://www.casperselectronics.com/store2/product_info.php?cPath=61_62_5_6_10&products_id=618

 

[Nick Micale]

Car starts fine and scan master shows 13.8-14.2.......... is this normal?

If you want an accurate voltage reading from your Scanmaster, then ground it at the battery, NOT at the dash.

To give you a voltage reading, the ground from the Scanmaster on the dash must make its way to the battery somehow with many connections and other items with lots of resistance?

 

[jragracer]

May sound dumb, but check your gauge fuse..Ithink its 10 amp

 

[jayp57]

I am with Nick here. Check the voltage at the alternator when the scanmaster reads low. This will verify a bad ground path causing a false reading or indeed a charging issue.