benjacob

Aaargh!!! For several years, I have been battling with my '96 S-10. The voltage gauge almost always reads around 11 volts. When I do a lot of shorter trips (ie. 20 miles or less), then after several weeks, my battery is not capable of starting my truck. Occasionally, after a longer trip, and the truck sitting at the curb for a few days, it won't start either (it will barely crank over a dozen times). I first thought it was the battery, but after having replaced it (2) times, each time with a better battery, the problem begins presenting again after several months. I just had the alternator tested at AutoZone, and all (3) test modes passed. What could be the problem??? Where else should I be looking? Thank you in advance for any suggestions . . . and Merry Christmas.

ps. I have checked for any potential drains . . . I even suspected that the under-hood lamp stayed lite after closing the hood, so I removed the bulb. No luck!

SABL

Hi Ben,

This could be a good question for Mack1.

If it were not for the fact that this issue has been happening for years, I would suspect the starter itself. Due to the longevity of this problem and the age of the vehicle, I would advise that you check all connections associated with the starter and alternator. It may not involve an actual drain on the system but an inability to keep the battery in a charged state.

Far too often, people discount the importance of the grounding system on a vehicle. Without a good ground, the total circuit is nonviable... it does not exist. The positive side will attempt to complete the circuit by actually making the jump as evidenced by "arc welding". Without a ground this would not be possible.

Maybe Mack1 or BG will jump in here..... they are very reliable and good friends.

In the meantime, check your connections at the starter and alternator. Look for any corrosion at all connection points and beware of any loose connections. With the replacement of the battery on 2 occasions, I think we can pretty much count that out as being the cause.

cardoc

Good day
It sure sounds like an alternator problem.While the gauge is reading that 11 volts try putting a volt meter on the large stud on the back of the alternator and a good engine ground like the alt case.Should be reading over 13 volts with engine running and accessores off. If it does put the meter across the battery terminals,it should read almost the same.If not look for a bad connection between the alt/engine/ground.
If you don't have the 13 volts suspect the alternator,loose belt etc.A logical approach with the volt meter (even a cheap one) will track down a lot of problems.
You can look for voltage drops across cables etc be hooking the meter in parallel to the flow of voltage such as alt stud to pos battery connector.Any cable or connection shouldn't read more than 1/2 volt.This also applies to the battery side terminal connections, always a source of headaches.
Good luck,Cardoc

mack1

Hi Ben,

Sorry I didn't catch the post earlier. A few months ago, I had a similar problem with an alternator. It measured bad on the Ford truck, but at Autozone, it measured good. (just like yours) Took it back home thinking I had a bad or loose connection, problem was still there. Still measured bad and no loose or bad connections. Back to Autozone and got a new alternator and it fixed the problem. With the new one installed, it measured 14.8 volts across the battery posts with truck running and engine speed up just above idle.

A cheap voltage meter will save you a lot of headaches.

I just re-read both SABL and Cardoc's posts and I think I just repeated theirs, except for my recent experiance.

Hope all of you had a great Christmas.

Very best regards,
Mack1