griffin1340

OK guy's I'm almost at wits end!
Last week I changed spark plug wires on my 3.0....fine, easy to do and all was well.
Next morning on my way to work I noticed that the amp gauge was reading low, head lights were a bit dim.
Bring it home and clean terminals on battery and put on charger.
Amp gauge still in about the 12v area of the gauge..usually in the middle of gauge more around 14-15V.
Next day the 'Rear ABS' warning light comes on and amp is below 12v.
Go to salvage yard and pick out a alternator from a donor '90. Notice on installation that the three wires leading from back of alt are corroded and actually a bit burnt looking. Re-wire the three [butt splice and new wire, heat shrink all.]
New alternator installed and amp gauge still in low to under 12v area [with load applied].
Have alternator tested at local garage. BAD!
Buy new battery...
Return to salvage yard and pick out another alternator.
Same thing but now I have more warning lights on on the dash. Battery, A-T temp & Brake warning lights.
My little multi tester [analog] looks to be telling me that alt is putting out 13.5-13.8 v @ 1500rpm.
But what is up with the warning lights?
Odds of two salvage yard alternators being bad? One was factory Toyota and the other was a re-manufactured unit.
I'm almost out of ideas, will probably pull newest alt and take to have tested tomorrow. If it's bad, I'm almost out of salvage yard picks.
Any insight into this problem?

Thanks.

eddieleephd

My alternator only puts out 13.8vdc so this is probably not your problem.

I would suggest checking all your grounds this could cause your issue!
I highly suggest pulling grounds cleaning applying dielectric grease and reconnecting!

most likely this will solve your problem.

griffin1340

Thanks, I've been tracking down & cleaning grounds but still have problems. Might have to look into a fusible link problem as well, I understand that if a f/l is bad it can return voltage and fry alternators [??]. I think that when I power up I am frying the replacement alternator...not good as the salvage yard is not buying that all the alternators are bad...no more replacements!
I pulled a '94 alternator from a SR5 P/U and its attached wires [different connector] and will rewire that into my '91.
Will try to use my currant alt. to trouble shoot.
Might bypass the fusible link [briefly] to check that out.
Considering my truck is 10 miles from home in a road side market parking lot now...I have some work to do.