QuestionWhen i start my 95 extended cab 1500 5.7 liter truck, it starts good, if i turn on the lights, the check engine light flashes at me the engine revs to 2 on the rpm scale to keep from dying, and then is normal when driving or turning the lights on or off, my battery guage has been moving if i turn the blinker on or off. the gas guage is now fluctuating back and forth not much but slightly, if i try to turn on the air conditioner and roll the window down at the same time the truck will act like it is going to die, yet it revs up and then goes on ticking. what the hell is going on??? I took it to the shop they kept it for two days, hooked it up to the computers and no problem could be found??? help
AnswerHi William,
'I took it to the shop they kept it for two days, hooked it up to the computers and no problem could be found'...WHAT!!!! You may want to find a new shop. I may be wrong (I don't think so), but I strongly suspect the alternator.
You need to get a volt meter. Test the voltage at the battery with the motor off. You should see 12.4V to 12.6V. Anything less is not enough. If you see 12.0V or less, the battery is bad too. If the voltage here is good, while testing the voltage have an assistant turn on the headlights. If the voltage drops rapidly, and gets to the 11's V, the battery cannot hold a charge.
If the motor off tests pass, start the truck. Check for the voltage at the battery with the motor running. You should see 13.8V to 14.3V, steady. Any more or less, is not enough. I suspect you will see this voltage drastically short. Once you have your reading, turn on the headlights. The voltage will fall off, and then the engine will 'race' to produce more current.
I could be a slipping belt, too. But I doubt it. You most likely have a bad voltage regulator. Easy to change. Two or three bolts, a plug, and a belt.
Heads up: The battery will be bad within 6 months from now. The battery damage the alternator caused is unseen now, but will come soon.
Hope this helps!
C J S
