89t295k

Ok , after the fouth alternator I'm getting frustrated.

When the car is cold it puts out 14.2 Volts and Battery is 12.3 when off.

I put a new regulator in the FD alt and it will still drop to 13.6V (Alternator+Battery))and 13.2 off cig lighter in car when it warms up.

FSM says 14.7 Cold and 14.1 Hot

My car runs like crap below 13.8V

So i get about 5 minutes of good run time before it acts up. (think the injectors start to lock up)

I also noted that when unhooking the battery cable it really runs bad---how can this be?

Any ideas?

HAILERS

Your 13.8vdc isn't bad at all in my humble opinion.

As the underhood temperatures rise, the voltage output decilnes.

Don't read the alternator output at the batt terminals, read it at the output cable on the alternator and your meters neg lead on the alternator body. The reading most likely will be different than what you read using the battery terminals.

Never eber remove the batt cable with the engine running.......unless you just like replacing regulators in the alternator as a hobby.

I added the jpgs to show how the ENGINE ELECTRICAL section always seems to refer to the temperature when the voltage output is given for a ...given test. Then added the second jpg to show how the FSM ENGINE ELECTRICAL section mentions the temperature gradient factor. There's a graph somewhere out there with temp vs voltage output ........but I'm not looking anymore for it.

rotarygod

iTrader: (1)

If you've gone through 3 alternators and have been having issues, it's going to be a ground wire problem. Until it gets fixed you're just going to keep killing batteries and alternators. Don't base your issues on voltage. A bad ground won't necessarily show up that way. It's the amperage that matters. If you aren't getting the current to the ignition system, you bet it will run bad. I'd replace several things just to be safe. Replace the ground wire from the battery to the chassis at a minimum as well as the block to firewall ground. While you are at it, add one from the battery to the engine block and one to a fender. Now upgrade the power wire from the top of the alternator to the battery as well as the power wire going to the starter.

I guarantee this is your problem. You've got all of the classic symptoms. It's an easy fix.

HAILERS

The attachment comes from here: http://www.aa1car.com/library/charging_checks.htm

89t295k

Really good info guys.
Thanks

I have not burned out any alternators , I just can't seem to get any of them to stay above 13.6-13.8 Volts at the alternator. I have two S5's and two S6's I keep swapping out. I am not 100% sure my problem is Voltage but, all I know is that as it falls below 13.7 and is getting hot it acts up.

I get about the same reading at battery as the alternator so I did not think it was the cables but, I am off to try the voltage drop test as in that web page.....hope to find a week cable.

This should be a sticky.

89t295k

.05V Positive
.13V Negitive

Both Below the .2V Spec.
It shows me that my positive connection is better than my negitive. So I will focus on getting them more balanced.

That is one sweet and easy test your cables.

gkarmadi

iTrader: (20)

do you have an underdrive pulley??