I've had this problem for a couple of years now but not sure if it is a real problem. My 94 LT1 voltage reading on the dashhas always been just above the red zone. It doesn't matter if the a/c is running and/or lights are on or off. I've rechecked it with a multi-meterthat shows I'm between 12.0-11.4v.I'm thinking it should at least be 13.5v. at idle. The engine always started even with this problem. I've checked and cleaned both pos and neg connections as well as the connectors going to the alternator. I haven't checked the terminal on the stater thinking it's ok because it always cranks up fine. The battery is 3 years old but don't think it's relevant. I haven't taken off the alternator to have it bench tested yet. Should I? what else can I check? thanks

 

Where were you checking when you got the 12.0-11.4 volt reading? Did you check at the alternator? At the alt. you should be getting close to 14v. And in the mid to high 13's at the battery (with engine running). If you're getting your low reading at the alternator, it's bad.

 

I'm reading at the battery. I haven't taken it at the alt. I've had alt with bad diodes before and the voltage was down at around 9v. so it was pretty obvious but I can't fiqure out howthis onesbeen running for a couple of years now. Should I takethe reading at the alternatorterminalwiththe wire disconnected?

 

Sounds like you've been pretty lucky and just breaking even.
A bad voltage regulator can also give you low output. BTW, your alternator is the new (CS) style that no longer has a diode trio.
You don't need to disconnect any wires to check voltage output at the alternator. If you have a low reading at the alternator, then it needs replacing or a rebuild. If low, you can test to see if it's the regulator or not by grounding the back of the regulator to the case which puts the alternator into a full output mode.
If output is already good at the alternator, (and it is low at the battery as you say), then you need to start checking all your connections between the alternator and battery.
These links should be helpful to you:

Delco CS Alternator

How to Diagnose

 

ok thanks