supercharged cobalt

ok so how do I fix it its to dark out and I gotta go to work at 5 am I can move the little push rod connected to the bypass valve it moves and all so idn I just wana have a damn car that works right

supercharged cobalt

I can push the rode and it goes up on the bypass valve

mrbelvedere

iTrader: (3)

take the vacuum line that runs from the intake manifold to the bypass solenoid off at the solenoid and plug it see if it will boost then if not check all vac lines if good replace bypass actuator

supercharged cobalt

ok so if it doesn't boost what does that mean after I plug it
are you saying to plug the hoes or to plug the port on the bypass valve

srmil

I did this and got 12 Lbs of boost..so what does it mean? bad solenoid?

srmil

Was only getting 4lbs of boost..I did this and got 12 Lbs of boost..so what does it mean? bad solenoid?

ROADKONE

I am reviving this thread as it seems as if no one has solved the problem. Now I'm here to create another one.

So... I get 4psi at WOT.
I get full peak boost when I pull the hose between the solenoid and boost actuator. Also when pulling this hose the solenoid is creating vacuum... Which leads me to make the claim the solenoid is always open and will not close.

I know my solenoid is good because I tested the brand new one on a SS/SC that works fine. I swapped the boost actuator/valve with working one and got the same boost issue result.

So now I can rule out a bad solenoid and a bad actuator/valve.

So now I turn to electrical. Is the connector to the boost solenoid supposed to have power (12v) all the time or should it only have power when a signal is thrown?
Is the solenoid connection a reference? So it has power all of the time unless the PCM cuts power, which would close the solenoid during WOT or increased throttle leading to peak boost and no bleed off?


I'm stumped here as everything works fine when I pull the hose off the solenoid that connects to the actuator/valve... Or when any of my parts are placed on another car.

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mrfitz

ROADKONE -

I am in the same boat as you. I replaced both the solenoid and the actuator. Also replaced all of my vacuum lines.
Like you, my solenoid is constantly passing vacuum, which pulls the actuator down and opens the BP valve.

2007 SS SC - ZZP Stage 2.

I'm thinking something electrical or electronic as well. Solenoid not getting correct signal. Or the PCM is not getting the correct info to judge when to send the signal.

Brainstorming:
- MAP Sensor?
- SC Inlet Sensor?
- Something reversed in the ZZP tune?
- Theres an AIR SOL relay, but I swapped it and no change.

Pulling my hair out trying to figure this one out.

mrfitz

Also, I am reading that the solenoid is supposed to be closed normally. Whereas for you and I it is open and vacuum is present. (My Solenoid is new also)


Quoting JMC007 on Cobalt SS dot com

"Most of the supercharged car doesn't have any other hose (like the lower one on our cars). On our cars, this hose is connected to the electrical selenoid which is activated only in specific conditions (like abusing conditions). The way it works : There is a pressure hose (which is connected to the intake manifold (after the compressed air) which is connected to the selenoid. This electrical selenoid is normally close. When the PCM tells the selenoid to open (a good example is when the PCM reads more than 12 PSI from a MAP sensor), the positive air coming from the manifold pass through this selenoid and goes to the bottom of the actuator. This pressure (higher than the actuator spring), forces the by-pass valve to open, which bleed the extra boost."

mrfitz

Figured this out. Finally. It was a bad PCM.

When I went to cycle the boost solenoid on and off with a scanner. It would not respond, even though the boost solenoid was new and bench tested before installing.

Swapped PCM's and Boom. The boost bypass system finally operates as normal.

Buddy

I have a 2007 cobalt SS with the stage three zzp and I'm getting the same thing only 4 ibs and when I unplug the solenoid I get full boost what can I do to fix this? I also have an o2 sensor maf sensor and throttle body position code and I've replaced the maf three time the o2 once and throttle body once I have no idea what to do.

mrfitz

Hook it up to a scanner, and see if it reads 05 or 06 in the vehicle info. 05 and 06 pcms are not compatible in a 2007 car. That was the ultimate issue for me.
Then contact ZZP, they'll help you figure out the PCM thing.

mrbelvedere

iTrader: (3)

get a new solenoid and get the tune checked

you can plug 07 pcm into an 06 or 05 the car will run if you plug an 05 into an 06 or an 06 into an 05 the fuel gauge reads backwards 07 into an o6 fuel gauge reads normal