Alternator / battery issues

Well the Roady is back from the transmission shop and running well, but it's stalling again. It did this the first time out of the shop, so my gut says the shop is running down the battery. It will stall while creeping in 1st gear, or when trying to accelerate from a stop. The first time it happened to my wife 3 times in a row which really spooked her. This time it happened to me, letting it run on a fast idle for 2 minute seemed to have helped.

I've put it on the charger again over night. I measured 12.57 volts before I put it on the charger, but it didn't have enough juice to start the car. Tomorrow I'm going to take it to O'Reilys and have them check the battery and alternator. It does show over 13V when running (per my test last week) but I'm not confident that the alternator isn't getting weak.

Anybody got a better test for an alternator than just looking for 13V while running?

A rebuilt alternator is about $150, more than I thought it would be for a B-Body.

My 93 Caprice is giving low idle stumbling/stalling problems that I attribute to bad cables (hoping to take time this weekend to change them out) and a cheap battery (new one waiting to go in with cables) and will start the engine when reading under 12.5 volts. Got a factory service manual and it plainly states get the ignition/fuel/charging systems up to par before blaming the tranny for this type of problem. Bad cables will cause a low charge getting into the battery from a fully functioning alternator and the full voltage will also not get to the electrical system through high resistance cables.

It does not sound like the battery or alternator. The fact that you can restart the car would minimize the possibility of the battery and cables. You imply that it will run once you get past the transition from stopped to moving.

Before doing an parts swapping, do you have any codes in the computer? Sometimes residual codes will cause errant behavior. Try getting your codes cleared. You may be able to do it yourself, by removing the fuse(s) for the computer and waiting two minutes before reinstalling them.

A friend of mine just had his wagon codes read, and afterwards the car's performance has been rejuvenated.

Also check youtube yesterday I watched a vid from GM re driveability issues with the roadmaster off idle stall was one of the issues it may help you look at some other possible causes. Good news is you have your new trans hope the major stuff is past you...Jeff

Fred, is there a thread here on how to clear the codes? Ours is a 94 so obd1.

Jeff, I will check YouTube.

Thanks all!

Update. After being on the chargwr all night I still got a click click click on the first attempt. Second attempt it clicked a few times then fired up.

I will check all the connections but then I think I need to have the battery tested. It is less than 2 years old per the receipt.

Other thoughts?

bad connection either at the battery,. or at the starter,. or ground to block etc,..

I doubt the stalling problem is voltage related,..

I checked the voltage at the battery while off (12.6V) running with no real load (14.7V) and idling with every electrical accessory I could think of on (13.7V) so it looks like the alternator is working.

So it probably isn't voltage related.

I will check the connections this weekend if the rain lets up.

I also had time to hit picknpull this morning and pulled a remote positive terminal to replace the one on our Roady that shows signs of overheating . That will be a good excuse to check and clean other connections.

I hope i don't need a starter. I just had to replace the starter on my Alfa, not my favorite job.

LT1 isn't too bad,..;et the starter hang on the positive cable while you do the trigger wire,.

not a very heavy starter either,..

I checked the connections at the battery, the negative was slightly corroded so I cleaned that up and tightened both of them.

The connection at the starter seems solid.

But the connections at the aux positive post were loose, and the plastic around it was melted. So I replaced that and it fired right up, took it around the block and no stalling.

I need to drive it more, but hopefully the aux positive post was the issue. It was obviously a fire hazard and needed to be replaced, but I hope I have killed two birds with one stone. Or wrench.

I hope you put a brass one in place of the original.

Yup, pulled a brass one off a 96 RMS at Pick n Pull.

Glad you found a simple problem that was easy to fix. I think I found my problem today after having time to check out the car. Pulled the vac line off the EGR and no more problem so I know where to concentrate my efforts now.