Thank you VERY VERY much for helping out. Here's where I'm my own worst enemy. I don't know how to do any of what youve stated!!! I'm good with mechanics, but dont know much about how to do any of what you suggested. Hell, I dont even know how to save your suggestions, save this thread, or post pictures to the forums I'm on. I'm close to 70 years old, and it's hard to learn this stuff. When I do, it's hard to retain it. Waaah, waah, wah!!! I know it does no good, and I hate admitting I don't know, but it's true. Anyway, the compressor does kick out at higher rpm, say 5,000, or thereabouts, under WOT. But maybe you've got it figured out. I'm pretty lost on tuning. Again, thank you for helping......

I think you just need to find another reputable tuner in your area and explain the issue. If your near the Tampa area, i have connections that might be able to help, just send me a private message. Im delving into the tuning world as well, but with Pro EFI stand alone ECU and not OEM ECUs. It can be all confusing at first, but its pretty cool understanding how everything "thinks".

Would be nice if you could have the tune read by someone with HPTuners (preferably 4.8.7 or earlier) and then post it here.
Those of us with tuning knowledge could easily compare your tune with a stock 2000 tune file and see if the AC section as mentioned above, has been mucked with.

Thank you for trying to help, Ron. I am a pretty fair mechanic, but even if I had the info you want, I don't know how to post it. Hell, I cant even post pics!!!

IIRC isn't there a WOT disengage on the AC as well,, I know my old GM truck would drop the AC when the pedal was above about 75-80% and wasn't at high RPM.. Just a thought..

Grinder, only way we can help is to see the tune file. I’m 66, you ain’t that old.

PDX, yes a wot cutout. It’s in the tune also.

Without seeing his tune, and I’d bet something amiss there, very hard to say. My hpt cable won’t stretch beyond Portland…..

Hey, Ron-Thats my line, lol. I’ve told some guys the same about my arms not reaching from Florida to Michigan, and vice versa!! Anyway, a guy on a different forum has found my original thread. Can't hurt to have another opinion. You have no idea how much I'd love to share that tune file with you guys. I'm sure I could get it from a guy I know with HPTuners. The problem is, how do I share it with you guys?? Do I take a pic of his laptop screen with my phone, then add the pic to a post? Or, do I have him print it out, and take a pic/pics of the printout page(s), then add to my post??? Thanks to ALL you guys for being so patient!!

It's 2022 don't you think it's time to take some computer classes? There may be some online courses somewhere. Not trying to be mean, you are missing out on so much by not knowing how to use a computer. The Tuning School has some great online tuning courses, but you will need to know how to access and save files to your computer.

You have your HP Tuners guy save your tune file as "any name you want.HPT" - then copy it to a CD or a thumb drive, etc. Then attach it here. You should have a copy of this file saved off somewhere anyway as an insurance policy against PCM failure. That way, you can load your saved copy into a future PCM if you ever need it - hopefully not.

Rick

This site makes it easy with the manage attachments function

GREAT NEWS, for me!! I've found the original tuner. He is at a place called Motor City Speed, in Michigan. Made up of former Wheel to Wheel Powertrain employees. Name is Rich, works with Billy Briggs Racing Engines. Both in the same building. I'll check with him, and if he can't figure it out, I'll have him post the tune on here. Thanks a lot guys. I'm sure some of you will be interested just what the heck is going on here!!

Sounds good. I hope he can fix it for you. Like you said if not post up and I'm sure someone here can.

Thank you so much, everyone who's tried to help out. It'll be a few months before I'm back in my home state. But I subscribed to this thread, and I promise to try to get the tuner to post the tune file. I'm sure he'll help me do it. I'll also report back if he knows what the problem is, and rectifies it, then I'll share that info, as well. If he did intentionally do this for a better idle quality, I'm sure my car isn't the only one he used this tactic on. After all, my car idles pretty fair. A 232/236 duration, .600" lift, 112 LSA cam is actually on the mild side for a 427. If it was in a 5.3, or 5.7, I'm sure the idle would be a bit rougher, and perhaps he did this to other cars to help the idle. Who knows?....

I know this is an older thread. But it has puzzled me, and many others for several years. SOLVED!! Turns out my 25% UD balancer, and idle rpm both are to blame. Simply put, the compressor wasn't spinning fast enough to make enough system pressure to satisfy the PCM that all was good in the HVAC system. The PCM didnt detect enough pressure in the system for the compressor to stay engaged. PCM thought it was low on 134a, and disengaged the compressor. My tuner is really good, and due to that fact, he is able to set idle rpm lower than some tuners may be able to. Combine lower idle RPM with a 25% slower system rpm, and it would cut out. Simple in hindsight, not so easy in real time. I switched to a somewhat more aggressive cam this time, and the tuner raised the RPM slightly, now around 900 RPM. All good now!!!