Turbo running poorly

[zdr]

My '92 Turbo S2 has been having issues.* When I accelerate between about 2700-3000 RPM the engine sputters/shakes and runs very rich (according to drivers behind me).* When I hit 3k it smooths out and takes off with the turbo spinning.* It has been doing this for a few years but was only mild and I thought only at higher altitudes until this year when more obvious and at sea-level.* Any thoughts on where I should start looking?
Thanks

[Cobalt]

Did you check for vacuum leaks in the CIS? If you try adjusting the idle on the throttle body and nothing happens start there.

How often do you clean out the old fuel in your tank and change the fuel filter? You might need to have your injectors cleaned.

Hard to say with these cars they are great when they run fine but can be a PITA to diagnose.

You might try posting this in the turbo section.

[zdr]

I think I may have already found the issue - the intercooler wasn't properly aligned so after replacing it correctly it seems to be running better. Will test it out more this weekend but I'm hoping I got off easy this time!

[Cobalt]

Originally Posted by zdr

I think I may have already found the issue - the intercooler wasn't properly aligned so after replacing it correctly it seems to be running better. Will test it out more this weekend but I'm hoping I got off easy this time!

If you have a poorly seated IC it can sputter or not run at all. The O ring has a tendency to enlarge and not sit properly. I keep a few in stock just incase i have to remove the I/C. GL