22psi stock tune.
 

I had the plastic fittings on my stock intercooler break and ran without boast for a week and now have the zzp intercooler on. For about 2 weeks after the install it was holding at 22.5 psi not just spiking and spooling a lot faster. It is now back to normal at 19 psi. Has anyone else had something like this happen and is there any way to get the 22.5 psi back or do I just need to turn it.

Sorry, but 22psi, where you live at, is not a stock tune. If you bought the car new and can verify it's stock, then you either have a faulty gauge or a BV problem. If it is stock, then it would(should) trigger an overboost CEL with boost numbers that high.

If you bought it used, then the previous owner probably had a tune done.

Fwiw. Around 19 is what I get with the GMTU. I'm pretty close to sea level like you are. Your's sounds like those are GMTU numbers.

Quick way to verify; look at the top of the MAP sensors and see if the sensor is marked with a sticker. Blue and white sticker means 3 bar MAP sensor and GMTU.

This:

Attachment 16634

Sounds like your car has learned down the boost quite a bit. For the hell of it, go under the hood and pull fuse #41 ( ECM fuse) which will reset the learn down. Put the fuse back in place and Go for a drive and floor it. I bet you will see 22-24 psi

Nope. Mine has pulled 19 since day 1 of the GMTU install. It has nothing to do with any of that learn down theory.

I have had several back and forth talks with some engineers at GM regarding this. In a nutshell, if it's making the power with 19 lbs, then that's all I'll get according to them.
The RPD does show my output to be right at the GMTU's 290hp, 315tq.

Well it worked with mine several times but maybe that's because I had a bunch of intake and exhaust mods. With GMTU I would max at 22 psi. Pulled the fuse and the first wot pull I see 24 psi. Then the next pull was back at 22 psi max. It "learns down" very quickly it seems. I know people say GMTU disable the "learn down" or whatever but I've seen it with my own eyes. Once the computer collects all the data it needs, it makes it's corrections wherever needed(boost timing, wgdc, idc, ect) my .02

There's no 'learn down"
Our ECMs are "torque-based".
Whatever the "torque-curve" is, in the "tune", is what the ECM is
going to do it's best, to follow.

The GMTU, + all aftermarket "tunes", of course, have better "torque-curves",than stock.
The ECM "learns" quickly, after being reset , to settle into it's programmed
"torque-curve".
That's why, with even a bone stock HHR SS, the 1st few minutes after an
ECM reset, your buggy will fly.
If you reset your ECM at the track, your next run down the track will
probaby be your best run of the day...:twothumbs:

The car is back to 22.5 psi and has been there for 2 days now. I'm guessing it is actually already tuned because I noticed the cruise control button got bumped off and that was the first time it was off since I got the car and I know some tunes us it to turn on. I bought the car used by the way.

"Torque based parameters adjustment"s , "learn down"- same same lol