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I would have to look into what's available to build them.What kind of failures are you seeing?can you do gt500 alternators as well? seems the 07/08s have POS alternators in them and high failure rates as well.
Malcolm,i'm not sure what else would cause it.Youve covered all the bases,is the locking clip still intact on the regulator plug?Battery wouldn't cause the light to come on.Jamie,
Maybe you have some ideas. My car had the stock battery and alternator still. I started getting the battery light under WOT.
So I purchased your optional 160 amp alternator and wire upgrade and also installed the 3.2 pulley. I also got a brand new battery. I still have the problem. I had given you a call and you suggested I get my alternator professionally tested by a real alternator shop instead of the local auto parts guys who typically don't really know what they're doing.
I did just that and the alternator shop says the alternator is good. I then replaced all the grounds such as from the engine to subframe with heavy 2 & 4 gauge cables instead of the flimsy steal braided factory stuff and I thought it had fixed the issue but it came back. I've noticed more recently it'll even do it randomly when idling but 99% of the time it's under WOT. Data logs show voltage dipping to mid 11s under WOT which is what's triggering the battery light on the dash.
I'm not sure what else to check. Maybe my new battery is bad and I should replace it again? The autoparts guys claim it's fine. They stick a meter on it that pulls a load for a few seconds and go no it's good, see you later. Not sure that's a good enough test.
Malcolm
What is the pricing for one of your Alternators?
Nope problem came back. New battery didn't fix it. However I did notice when I take it out and hammer on it, it seems like it's only the first few pulls it does it then stops. That's exactly how my last new battery started out and slowly deteriorated. Is it possible for the alternator to be killing my new batteries?
You battery needs at least 12 volts from the alternator to replace the power that the battery is using. (these cars use every bit of 12 volts) If it does not have the 12 volts your battery will start to drain. With everything running well you should be charging at 13.5-14.0 volts. Usually when you are charging any lower then that you have a weak alternator.
Hope this helps
You battery needs at least 12 volts from the alternator to replace the power that the battery is using. (these cars use every bit of 12 volts) If it does not have the 12 volts your battery will start to drain. With everything running well you should be charging at 13.5-14.0 volts. Usually when you are charging any lower then that you have a weak alternator.
Hope this helps
My original alternator went bad so I recently got a Start 'n Charge. I am having the exact same problem with the battery light now. I have a new Motorcraft battery AND a new Start 'n Charge alternator, both installed within the last several weeks. It does not happen every time, but I am getting the battery light intermittently under WOT/high rpm. Starts as early as 4,000 rpm sometimes.
I wish I had an exact answer to the high RPM light problem.I've seen it on a lot of units,not just mine.I've been thinking it over for quite some time, and have come up with an idea.:idea:
Stock units use 25amp soldered button diodes.
The rectifiers I've been using have spot welded avalanche 50amp press fit can diodes.Very heavy duty.
All diodes leak at a certain amperage,hence the rating. With the 200amp stators i'm using (I call them 160amp but they are marketed as 200amp) I'm thinking POSSIBLY they are leaking at full output , which could trigger the light.
I can't prove it on the bench,it's just a thought at this point.
So I found a place that makes a 70amp diode version rectifier,I have 3 on order & will get those built,first one will be to replace yours & see if my theory is correct.
It's just strange how this only happens on a small number of units I sell.It's only the 03-04 Cobras,the V6 GT's work just fine,same alternator besides the pulley.But I do see it as a problem & am looking to eliminate it for once & for all.