Here's a cut and paste of an ad I ran so maybe the info on it is helpful. It's pasted at the bottom of this page.
Basically, I'm pushing 60 and on a fixed income. I asked around when attending auto shop classes at a local tech school about what the "kids" had to say when I was thinking of buying a used car. The Cobalt SS came up and so happens when I looked on craigslist I found one in my price range. What a blast this car is. I have found some joy in driving again. I've had it 2 years now. Me and my shop teacher feel that these codes and limp modes are due to "something" out of whack that someone did. There is a cheap-fender-well aftermarket cold air intake. From what you guys are saying I'm now thinking that a tune wasn't' done after installing this "thing". My next move appears to be taking the air intercooler out and doing what needs to be done with all that, if that is the problem.
Here's what I'm thinking I can afford to do next. Change the cold air intake to one that fits in the engine bay with the MAP closer to where it was when stock. Then go get a tune. Any thoughts on that? I'm trying to keep it going because it is my daily driver, on a shoestring budget so I don't want to have to park it.

Ad I ran:
This car is my daily driver with a few issues. I’ve owned it for over 2 years. A few times a day I have to use my OBD and an app to reset the sporadic codes that come up. I can reset the codes while driving. I am told this is from a leak somewhere in the intercooler plumbing. The intercooler passed 2 smoke checks. The turbo boost is 25 lbs so It appears some sort of mods were done. It happens when fully accelerating and at 25 pounds boost that this happens when I hold it at that 25 lbs for long. I bought it off a lot in Atlanta and do not know any history except from a VIN search showing no accidents and what appears to be 2 other owners.

 

What are the codes that you keep getting?

 

I haven't been doing much driving this week. So far, these are the recent codes: P0013, P0014, and a new one P0106. Usually the turbo boost sensor circuit code, P020?, comes up but hasn't had a chance yet. The turbo boost sensors, there's 2 right? were replaced and wiring checked several times. A smoke check was done twice. MAP sensor replaced. Both times doing the smoke check the only leak was very faint around the aftermarket BOV. That was stopped by putting a washer with the internal spring to tighten it up.

 

For the p0013/p0014: https://www.cobaltss.net/forums/prob...ng-off-310432/

For the p0106 I'm fairly certain it's the map sensor on the cold side charge pipe below the intake manifold. Could be a bad sensor or wiring.

 

You're awesome. Great info. I can do a resistance check! Now that I know what to check, lol. Thanks man. I'll post when I get er done...

 

smoke testing for boost leaks doesn't work, boost leaks can appear at any pressure. for instance I had one that only showed up at like 20 psi. smoke testing doesn't pressurize to high psi that I know of. you need a proper boost leak tester and pressurize the system to the psi you are boosting too to see. make sure oil cap is off when you do.

 

Great reply. Thank you. That makes total sense. My tech school had no such way to check under pressure. I do have some easy things I can do for now. Thanks to the replies I've been getting. Like checking resistance on cam sensors. Those codes are now what I'm getting. I've also found a few hose clamps that are for radiator hoses so I now have the proper clamps that are correct and will be replacing them.
I also now believe that I'm posting in the supercharger thread and am trying to transfer my post to the turbo side. You all have been really cool about it by not shaming me, lol. Thanks again.

 

you are in the turbo section, another mod must have moved it.

 

25 psi is definitely not factory boost, if your wiring checks out may need the upgraded boost and map sensors that can measure more bars. I think you may need a retune after that but I could be wrong. Im running 23 psi on the stock sensors and have been lucky. Zzp performance sells them