electrical demons running amoke

[lincster2]

Lately my ride '92 MTX has been acting like it's "Christine's" electrical cousin. Last month replaced the alternator with another rebuilt alt. from Autozone, since then the battery light sometimes comes on. (The newly rebuilt alt. had a smaller pulley, I figured the internal voltage regulator should take care of any extra power safely.) The first week not so much, so had it tested at AZ, both battery & alternator passed. Week & a half later battery light comes on more often & longer, tested again same result.. passed.

So 2 nights ago Battery light on as the new usual.. headllights, radio & vent on wizzing down the freeway.... then all of the sudden the lights (both headlights & dash lights) gets the brightest I've ever seen on this car. A few years ago relaced stock headlamps with silverstars didn't notice any change in light output.. really dim. So now the car's lights are shining so bright it's like a new car's lights.. I was thinking Yaaahhhh...great ...... but a few seconds later the vent & radio power stops... wtf.. a few seconds later the lights goes back to being lame dimness & power returns to vent & radio.

At times the vent/fan goes all *** on me. The fan blower never was never very strong on this car....... but lately the fan output gets really strong, for a few seconds then dies .. a few seconds later it come back on usually at normal weak output ... then it blows like Irene/Katrina then dies.

So before I take the problem child to the car doctor any tips, hints... advise?

 

[hawkeye18]

Your replacement alternator is bad. Unfortunately, replacement alts for the SHO are bad more often than they're not. I do hope you got one with a lifetime warranty.

As for it having a smaller pulley, it's possible that the old one had an underdrive pulley on it. Shame you turned it in as a core.

 

[lincster2]

Yup.. most of the items I buy for my cars are with the lifetime warrantee.

 

[lincster2]

Replaced the alternator today. Took it down to the local Autozone & had it bench tested, after only a few seconds the testing machine stops..... 3 large FAILs pop up on the tester's screen. The AZ guy & myself stare at the readings.... the crappy alternator was pumping out over 28 volts!!!

Now I know why everything was going beserk electrically. Hope that it didn't fry anything......come to think of my A.C. dosen't work right . On max ac it pumps out really hot air.

Well live & learn... don't buy cheap .... it might bite you in the ass.

 

[hawkeye18]

Your last issue sounds like the most dreaded issue of all... blend door actuator. When it fails, it fails hot for safety in the winter. It's a $20 part that the car was built around.

 

[93markVIII]

on the dead alternator, its probably a bad voltage regulator. easy enough to replace with out buying a whole new alt. (unless you have a warranty of course.)

 

[lincster2]

Bad regulator

Well since I had bought a alternator with a lifetime warranty.... no worries.
I assume it was a really bad voltage regulator... 28 volts seems a wee bit high don't cha think?

My ac/heater seems to have magical self healing powers..... it's now working just fine.