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Hi all, I have installed a new 3G alternator on my '93 and I am still getting the same results as before the swap. When I have the air on and blower on high all is fine but if I have to turn on the lights then everything gets dim and the blower gets slower. I have everything wired the way I am supposed to and I even have 4 gauge cable run from the alternator to the battery to make sure it is getting all it can. Whats the deal? Oh yeah, everything is factory all the way down to the headlight bulbs, radio etc...

Scott
 

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keep in mind the whole reason the 4 gauge wire to the battery is there is because the cars stock harness cant handle the bigger alternator. if you have a bad ground or a nicked wire you could be drawing high amps to what ever part of the system thats causing the problem and that being on the stock harness .... does the lights only cause a problem ?? does it only do it with the defrost or air on , with the blower on high?? i still have an issue with my car if i turn the fog lights on for longer than a minute ... ide go thru and shine up as many connections as possible on the lights harness use some dielectric grease on the contacts .... check out the amp draw on the ac compressor it could be high too clean up the grounds the one coming from the front and the back of the block to make sure you got good contact to the fire wall and the fender well .. heck if you can find out what the amp draw is supposed to be on the blower and check yours ... all it takes is one thing to give ya hell .. good luck
 

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What are you running for pulleys? An alternator is usually setup for 2400 rpm curve before it starts to make much for amps. That is alternator rpm not engine. If you are using stupid aftermarket under drive pulleys--there you go. Bump up your idle to 900 or maybe 1000 and you should see problem go away if you are on the edge.

Also, a lot of 3G aftermarket alternators are complete crap. They are nothing more than stock. You could take it in and have it checked across the RPM band to verify it actually is doing something. I was pissed to learn my Powermaster was a reman POS. Supposed to be 200 AMPs, what a joke--Chinese CRAP.

A simple test is voltage drop from alternator to battery to look for problems in wiring. It should not be more than 0.5Volts from alternator to battery. Wire gauge means **** if the connection is crap, the connection is almost ALWAYs the weak link.

Invest in a clamp on DC amp tester to find sources of high Amp draw. I got mine off Ebay for $40, it is pretty cool for all kinds of diagnostics.
 
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