my 97 rodeo is goin crazy on me! normally, under heavy acceleration the alternator stops charging the battery to help with fuel economy. well, about a week ago when this would happen the voltage would drop to around twelve as normal, but also the battery, 4x4, and brake lights come on and the a/c cuts out as well. when the alternator would kick on after acceleration, everything would return to normal. over the course of the week, it got increasingly worse, the alternator would cut out under any acceleration at all. and now it isn't charging the battery at all. so the car runs with the battery, 4x4, and brake lights run constantly and the a/c doesn't work. the rodeo runs perfectyl so i have been swapping out batteries and charging the spare overnight the past few days, but i really need to get this fixed. it doesn't sound like the alternator is dead to me, but possibly a short in whatever tells it not to charge the battery under acceleration? i could really use some input from anyone who has any ideas. thanks in advance.

adam.

Trust me this DOES sound like an alternator failure!! I spent my whole summer experiencing this SAME exact nerve racking, rip your hair out, bite your fingernails, agony.

TRUST ME, it's your alternator! I too have the 97 model year, 3.2L.

BUT, when you go for a new one, do NOT get a remanufactored one - they will not put out the charge that these Rodeo's require.

I can tell you too, that although your alternator may not be dead, yet, that truck KNOW'S something's out of loop - and it will kill it. These darned Isuzu's require very true and precise electrical current, and if anything is even just a tad below par, it'll finish it off quick!

I'm now almost 2 weeks running on a new BOSCH alternator, and it's made a world of difference, and I too had to replace my battery. One thing I've learned is that they generally both go at the same time, only they can be deceiving, in the fact that, under a volt check, your alternator will probably say it's fine.

But if you're eating through a charge on the battery, chances are that alternator's gone; and these darn trucks will continue to run without one. I came 175 miles on a totally dead alternator 4 mnths ago pulling a boat and all; and have been driving over 6k miles this summer on one that was putting out half what it should (remanufactored junk).

Post back here after you decide what to do.