Can't seem to stay away. Not complaining though, it's good to have a place that offers such reliable advice. Thanks again in advance.

I have a 2001 DRV 3500 5.9L maxi. About a year ago my dashboard gauge voltage needle would drop down sometimes. All connections were checked including at the PCM. The "check gauges" light would come on and chimes ring. Voltage test at battery verified there was a problem. With multi-meter at battery terminals voltage measured; 12.0v everything off, 11.7v ignition on engine off and 11.4v engine running @ about 2000 rpm's. During these same tests the dash gauge would read about 11.3v ignition on engine off and with engine running start at that same 11.3v for about 10 seconds then bottom out all the way to the left which reads 8.0v on the gauge stop.

Back then this was infrequent and intermittent. If I pulled over and waited an hour everything would run fine for a month or two. Then it appeared for a 3 day duration. I parked the van and bought a new alternator and used properly re-flashed PCM from eBay. Before installing them I checked one more time and everything was fine and stayed that way for over half a year and some 6,000 miles. I returned the alternator but kept the PCM

Fast forward to present and I get what feels like this very noticeable miss. Once or twice each mile it seems the whole electric system including spark "blips out" for a very very short time but feels like a strong miss. Again all connections were checked. This came about all at once. The ignition parts were replaced with good parts some 10,000 mi. back w/ no problems.

So I swap in my new (used) PCM to see if that's the problem and on first firing it up I'm back to my charging problem just like before. I clean the 3 PCM connectors with isopropanol alchohol and add extra hold on them with zip ties but no good still. I swap back to my original PCM and now same problem with it.

Thanks for hanging through all this background but the question is fairly simple. I don't want to chase "gremlins" here- not "how to" but just "if"- is it possible to bypass the PCM and just put in an "old school" voltage regulator?
If yes maybe a suggestion for what kind or like off what other vehicle might a suitable regulator be?

Ooops, 2nd question. Circumstances have me living in my van now- it was well set up for that. As I drive around for parts or whatever, to keep a charge can the alternator be hooked up directly
to the battery in some process so I can charge it and get the 50 more miles I do on battery alone. Like parked with my multimeter hooked up to know when to disconnect direct alternator charge?
thanks.

 

A slipping belt will cause the voltage issues you're experiencing, but you never mentioned if the belt or tensioner were replaced.

 

Thanks, belt and tensioner are new and working fine. I just added a second question editing my original post;

"""
Ooops, 2nd question. Circumstances have me living in my van now- it was well set up for that. As I drive around for parts or whatever, to keep a charge can the alternator be hooked up directly
to the battery in some process so I can charge it and get the 50 more miles I do on battery alone. Like parked with my multimeter hooked up to know when to disconnect direct alternator charge?
thanks."""

 

Did you check your ground connections? Sounds like a wiring issue not a faulty part because it was intermittent now just worse.

 

Yes I checked the wiring.

Barring advice against from this site I'll soon be ordering the external voltage regulator kit from "Quick Start". Thanks

 

Thanks for your help. The external voltage regulator kit is ordered so I'm down to only question no. 2.

I've heard it called "full fielding"- is there a way to bypass the PCM (or not) and safely, by some process, directly charge the battery with the alternator. I could do this charging parked with my multimeter and then disconnect that direct connection and get about 50 miles on battery alone. Thanks

 

I think 'full fielding' would tend to have charging voltage rather high..... and potentially burn up the alternator, and/or battery.

 

yep, thought so- thank you once again sir.

 

Turned out it was the alternator as "Hey You" predicted (thanks). I've got the external voltage regulator installed (bypassing the PCM) and will continue to use it. Problems with it and I'm all set to splice back in the PCM. I don't know if this is common but alternator failure was intermittent which threw me off. I mean like 5,000 mi. between issues.
Last thing I have to do is return this clicking remanufactured alt. to Autozone and get a new one.
Thanks