Author Topic: 1.9 aaz electrical issue 92 jetta (Read 4634 times)

trent77 · « **on:** December 14, 2007, 07:37:58 pm »

When I am driving my jetta, sometimes my headlights get brighter and then my radio shuts off, and the heater blower motor turns faster. then it goes away. The alternator is very new, and it has the ratcheting pulley. I would love to test charging while it's happening, but it's intermittent. It does seem like there is drag on the engine when it occurs, at least the idle changes slightly. thanks for all your help.

bigblockchev · « **Reply #1 on:** December 14, 2007, 08:37:50 pm »

If you mount a voltmeter inside the car you can check to see if it is charging while driving. You should be getting 14-14.5 Volts when charging any more is too much. If the idle really does slow down you should be seeing a higher voltage when this happens. If you transplanted the engine into the car I would be concerned about the condition of the various grounding points. It is easy to overlook the necessity for several ground points from the engine to the frame. Improper or poor grounding can fry stuff right and left and cause weird instrument readings and flickering lights etc. Cheers Dan

MikkiJayne · « **Reply #2 on:** December 15, 2007, 02:50:33 am »

It sounds to me like your alternator voltage regulator is failing and trying to put out too much voltage. Your headlights getting brighter and fan getting faster are good signs of higher voltage, and the radio is likely shutting down to protect itself.

I would first try cleaning up the alternator mounting points and grounds as Dan said, then look the regulator itself. It may be mounted on the alternator badly, or have corrosion on the terminals, or it could just be faulty.

Mikki x

somolovitch3 · « **Reply #3 on:** December 15, 2007, 03:36:22 am »

Just how many Amps does your radio pull? Big amplifyer?

The running voltage should be 13.8 IIRC>

trent77 · « **Reply #4 on:** December 15, 2007, 07:09:16 am »

no my radio is just that, with cd. no amp, nothing big at all. The alternator is very new, and I believe it is 90 amp, it was on the engine when I did the swap. I will check all connections today and post a reply. thanks for your help.

trent77 · « **Reply #5 on:** December 15, 2007, 08:49:29 pm »

pretty sure I found it. Bad ground at transmission. I was going to clean the connection, when I went to loosen it, it was pretty loose already. I took it for a drive today after fixing the problem, not a problem. thanks for the input.

bigblockchev · « **Reply #6 on:** December 16, 2007, 01:28:15 pm »

Glad to help. Cheers Dan