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'96 Rodeo idiot lights making me feel stupid

My new battery was draining down overnight. Thinking it wasn’t charging back up properly I replaced what I’m sure was the original alternator. Now sometimes the engine lights (battery,brake & oil) flash on and off when I accelerate. So far the battery hasn’t gone dead again.
I also had an oil change. They put 5.7qts in the 6 cylinder engine.

The alternator is most likely the model with a wide open throttle bypass. The designers, in an effort to give maximum response when accelerating, wired the voltage regulator field circuit through the ECM to turn the alternator off when accelerating. That system seems to be a permanent glitch and many alternators have been needlessly replaced because of it. Of course the internal regulator can fail to reset when triggered and cheaper rebuilds would very possibly have poor quality regulators. How familiar are you with solid state electronics?

BTW, when you bought the alternator, did the store ask you or inspect the old alternator to determine how many pins were on the field connector? And of the 2 possible choices yours had the connector with the greater number of pins, I assume.

I really hate it when the OP: doesn’t reply to let me know if I am on track with my advice. I would make an effort to look into the problem if there were some feedback. Oh well…

Sorry Dude I appreciate your input but I don’t live online.
You may be on to something. Yes he looked and I believe 5 pins was the result. I double checked they were the same. I also looked thru other replies on the subject and checked the belt it’s not new but felt tight.
Thanks for you quick feedback. I figured I’d have a bit of a wait for replies.
Is there a way to check if I’ve got one of this type? Reciept says MPA 13745 they kept the box for the core.


QB is the co.

I didn’t wish to sound critical, JEB, but so often people drop in here with a pressing problem and their problem gets numerous answers and no feed back. Oh well, Such is life. It does appear that you have the troublesome alternator and I would suggest that you return it for a replacement or a refund to replace it with a different brand. Your problem is one that I have been beat over the head with a few times in the past and my best results were from using the AC Delco rebuilt unit. If the current alternator often fails to raise the volt meter well above the 12v level immediately after starting until the engine is gunned, sometimes repeatedly, it is most certainly the voltage regulator that is integral to the alternator that is failing. But do be sure that the field wire connection is fully inserted and that the wiring harness is not stretched and in a bind.

many thanks Rod
Wondered why it came with a roadside assistance policy lol
I’ll have them check the install first
it’s been in less than 30d but I guess I’ll have to eat the labor