RE: ELECTRICAL SYSTEM PROBLEMS WITH VOLTAGE

I just went through this on my '95 Monte. Mine turned out to be bad connections at the power distribution block.

First thing I did was test to see if the low voltage was system wide. I did this by checking the voltage at every fuse and isolating which ones were at the low voltage. Only a few were at the lower voltage and others were normal. The voltage at the battery was also normal. This lead me back to the power distribution block beside the battery. I took it all apart, cleaned it up and all is like new.

Here's a link to the thread:

Try checking the voltage right at the battery. With the engine at a fast idle and no accessories, then at a fast idle with headlamps on and the heater blower on high. If you need a meter, Harbor Freight has them for around $4.00 on sale. There are more tests to make but start with these. One seemingly obvious thing a lot of folks miss is the belt. It has to be tight.

Al

Other than I'm lost. Any help?

Check your ground...from the battery to the frame.

Before changing another battery or alternator: Clean the terminals. Check the pig tail from the distributor for damage or a lose wire in the connector. Get 'em warmed up, and take a trip to a autoparts store that has a battery & alternator in vehicle load tester. Have it checked. Have them run the test a few times try different accessiories. Charles

THANKS FOR YOUR REPLY BUT I ALREADY DID THAT. AND I 'VE EVEN REPLACE IT

WHAT YOU WROTE SOUNDS LIKE IT WILL FOR ME BUT I NEED YOU TO WRITE THE INSTRUCTIONS DOWN FOR ME STEP BY STEP AND WITH MORE SPECIFIC DETAILS IF YOU MAY ...PLEASE .. EMAIL ME THANKS IN ADVANCE!!

I DID THAT ALREADY AND IT READ JUST FINE.. AND I STILL HAVE THE SAME PROBLEMS.. THANKS FOR TRYING TO HELP ME..

I ALSO DID THAT. I EVEN HAD ADDITION GROUNDS INSTALLED TOO. AND THAT DID NOT HELP..

I'LL CHECK THAT TO SEE IF IT'S A PROBLEM THANK YOU FOR YOUR REPLY!!!

I think it might help to quote the original msg. in your reply... so that others in the group could see the question and the reply and provide additional information if needed.

you can configure your newsreader to do this automatically.

I had a similar problem on my 95 5.7 K1500 trailer towing package several weeks ago.....was getting low voltage and had a leaking battery terminal. Replaced the battery and the starter went out the next day, don't think it was related as I just replaced it 6 wks before (200,950 miles on the original starter!), just a bad rebuilt starter. Anyway, replaced the positive battery cable that goes from the battery to the drivers side firewall distribution box as it was corroded from the inside from where the battery had been leaking into it. The trailer towing package has two positive leads that go to the positive side of the battery. One goes to the starter and the other goes to the firewall distribution box. Cleaned all connections and still had the fluxuating voltage. Would crank right up first in the morning then later wouldn't crank at all, would just click. Would tighten up the battery terminal, and would work fine for a little while and start the whole process over. After overtighting the terminals on two batteries and causing the positive side side mounts to come out we found out what the problem was. The lead spacer that goes between the positive side cables to the positive side post of the battery had been squashed down to less than a 1/4 inch over the years. I put in a new spacer, it is like a half inch or more in thickness and now that has fixed all of my electrical problems. What was happening with the old spacer was that when I tightened down the terminal on the positive side the long battery bolt would go thru the side mount bung and poke a hole thru the battery. Thank goodness for O'Reilly's liberal battery return policy, as it took two batteries to discover what the problem was. Now both the terminals are good and tight and I get a solid 14 volts in the middle of the voltmeter all the time now. This is a little long winded but hopes it might help someone out there......Mark

"Bullet" wrote in message news: snipped-for-privacy@g44g2000cwa.googlegroups.com...

The lead spacer is a typical problem. It can also cause alternator failures.

Cheers

This is normal. Believe it or not. The alternators are set not to deliver full power at idle so they will not fail in hot weather.

One way around this is to get a smaller alterantor pulley. Since you changed the alternator, you may have gotten a larger pulley by mistake. You can calculate the rpm needed, then using the diameters find a smaller pulley that will help. Dont go too small, as the alternator may then fail because it will be subject to higher rpms are higher engin speeds (4500 rpm). I believe 8000-9000 rpm is the upper limit.

Another approach is to replace the alternator with a larger unit, such as those used on police and fire vehicles.

Good luck

fail in hot weather.

Erroneous statements.

An alternator outputting 10.5V at idle is NOT normal. At idle, an alternator will put out anywhere between 13.0V and 14.5V depending on load. If the battery is at a low charge, you can expect to see around 14.5V. If the battery does not require any charging and there is no big load (ie high beams, rear defogger, large stereo), expect to see 13.5V or so.

What is the source of your information?

Steve

as you say above the alternator has to put out over 12.v at idle to charge the battery. At idle once again you should see around 13.v if the alternator is working properly. I believe the amp output changes with rpm and load.

You seem to have left out the fact that th OP stated that 'Under load' the voltage drops to 10-10.5 volts at idle.

Yup, was I supposed to include that in my response?

voltage drops to 10-10.5 volts at idle.

Although, this is GM's response to the problem:

Regardless, if it didn't do it when it rolled off the assembly line, it's not normal and it can be fixed.

Steve