Cobalt_SSTuner

iTrader: (1)

So, a few days ago i was driving my car, and I was getting belt slippage (SP?) so i popped my hood and lone behold, i dipstick was popped, and oil was everywhere. First thing i thought was ****, pistons? Then my buddy pulled up the gm service bulletin about the faulty intake manifold gaskets. Replaced it, car runs great, pulls hard no issues. Well tonite, same thing happened, about half a quart of oil sprayed on my motor, dipstick popped. The thing is, my car runs fine but when i go full boost it shoots some oil out.

Here is my thinking:

1. If it was a piston, the car would run like ****, and when its not shootin oil, it pulls like a ****.

2. Could the BBV be causing this? (BBV= boost bypass valve) Because when we were tuning, we "shut it off." And by doing that i'm seeing higher boost numbers, but i'm running a 3" pulley on 60lbers (waiting on my 2.8). Because if i'm not mistaken the boost bypass valve releases the pressure when you let off the gas, but if you turn it off, where does the pressure go when you let off? Out the dipstick?

3. I'm running a little rich, because we've been playing with my tuning, there is 0 knock, intake temps are normal, no trouble codes.

My mods are intake, 3" pulley with 60lbers, and catback exhaust.

I found this thread and was reading through it...

https://www.cobaltss.net/forums/show...+piston&page=2

Any Ideas?

2006BlackSS/SC

sounds like they diddnt get the gasket fully off the orginal

i had same problem. im fully stock and my car did the dipstick thing they replaced it with new gasket and it worked..

friend had to repace his 2 times the second time was cause of not having the gasket removed 100%

hopes that helps

Cobalt_SSTuner

iTrader: (1)

yea, Thanks for the idea, i'll have to look into that.

Coblasts

I dont think you should be shutting that off.Dont most people modify it to give higher boost number.
You cant control the boost without it,The highs when letting off the gas quickly etc.
Your probably blowing the intake gasket because of that ,
you said that you drive around with the bypass shut off ?
Operation
Supercharger boost pressure is regulated to prevent engine and drive train damage. When the engine is operating under high boost conditions, the powertrain control module (PCM) limits boost pressure to 83 kPa (12 psi). The PCM disables boost under the following conditions:

• When reverse gear is selected

• When the engine coolant temperature (ECT) is excessively high

• When drivetrain abuse is detected

• When the vehicle is decelerating

• If an intercooler pump failure is detected

• If the intake air temperature (IAT) sensor 2 becomes excessively high

• Under heavy load in first and second gear at engine speeds above 5,800 RPM

The PCM controls boost pressure by using the boost control solenoid. The boost control solenoid is normally an open valve. Under most conditions, the PCM commands the boost control solenoid to operate at a 99-100 percent duty cycle. This keeps the solenoid valve closed and allows only inlet vacuum to control the position of the bypass valve. At idle, engine vacuum is applied to the upper side of the bypass valve actuator, counteracting spring tension to hold the bypass valve open. As engine load is increased, engine vacuum is decreased, causing the spring in the bypass valve actuator to overcome the applied vacuum, closing the bypass valve and allowing the boost pressure to increase. The bypass valve starts to close when the vacuum measures 250 mm Hg (10 in Hg) and is fully closed at 90 mm Hg (3.5 in Hg). When reduced boost pressure is desired, the PCM commands the boost control solenoid to operate at a 0 percent duty cycle. This opens the solenoid valve and allows boost pressure to enter the bypass valve actuator at the lower side to counteract the spring tension, opening the bypass valve and recirculating excess boost pressure back into the supercharger inlet.

Results of Incorrect Operation
An open boost control solenoid control circuit, an open ignition 1 circuit, or boost control solenoid valve stuck open will cause reduced engine power, especially during wide open throttle operation.

The boost control solenoid control circuit shorted to ground, boost control solenoid valve stuck closed or a restriction in the boost source or signal hoses will cause full boost to be commanded at all times and a possible overboost condition during high engine load situations.

A restriction in the vacuum signal hose to the bypass valve actuator or a stuck closed bypass valve will cause a rough idle and reduced fuel economy.


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bigjoe25

well i had two cracked pistons and my car ran fine but would push the dip stick out from time to time so it could be the pistons