I have a 06 Cobalt SS/SC and after 4 months of having the car I started not having any boost. While idling and lightly accelerating the boost gauge moves through the vacuum section as it should, but once on the throttle the gauge hits zero or slightly below it and stops. There is a difference in the car so it's not the gauge.

I have done some flipping through other threads about the issue and it seemed to be the bypass solenoid. I swapped that out but still no boost. During regular driving the engine doesn't pop any codes, but when driving 'spirited' they come up.

The codes that come up are:

P0033 Supercharger Bypass Valve Solenoid Control Circuit -PCM
P0101 Mass Air Flow (MAF) Sensor Performance - PCM
P0103 Mass Air Flow (MAF) Sensor Circuit High Frequency -PCM
P0171 Fuel Trim System Lean -PCM
P0443 Evaporative Emission (EVAP) Purge Solenoid Control Circuit -PCM

I disconnected the vacuum hose that runs from the intake manifold to the solenoid and plugged it and went for a ride. The actuator stayed in one position and the boost was back so I'm assuming the actuator is fine. The boost was getting like this only went to about 6psi though.

Since I already replace the solenoid I'm at a loss for what it could be.

Any insight would be greatly appreciated.

 

Replace the EVAP solenoid. You would be surprised how many other issues that ****** can cause lol

 

I'll give it a shot and post the results when it gets done.

 

Le Bump, for other opinions.

 

Did you do it or not?


Go do some work instead of posting more questions when you are already getting answers.

 

No I didn't get a chance to today.

I was just trying to see if anyone else had any ideas before I run out and buy another part, no offense to you.

 

I could have told you from the beginning that it was not the bypass solenoid. What do I know though.
Good luck in your search

 

So I have the EVAP solenoid on order, should get here by Friday ($14 on amazon with free shipping )

While just driving easy home from work today the CEL came back after I cleared the codes on Saturday.

The P0033 (bypass circuit) and P0171 (bank 1 lean) popped back up.

Does this support the EVAP solenoid solution or point towards something else?

 

Hey man idk if you still read this thread but I had a hole in the CAI which explains the MAF codes. Since replacing the EVAP solenoid that codes hasn't been back.

The only thing I have left is still getting no boost and still getting code P0033. Any more ideas?