2.4 cobalt -- MAP issue

[jeanb]

One of the members of my CAR CLUB
recently had his cobalt SS (2.4) suddenly start to sound like a
Subaru WRX .... not good He's seen the GM dealership and they
can't ( or won't) figure out the problem

Attached is a log of his car
HE has minor mods - cold air intake - exhaust -

I believe he has compression issue - I will be bringing the car in with
him - he's young and I don't believe the Dealership is handling his situation correctly

Am I wrong ? Does anyone see anything else or is my analysis correct ?

[Baldturbofreak.com]

When an inline sounds like a subie you got a man down!
Do a leakdown test on the motor. Chances are your going to find some beefed lands. The MAF and MAP were gyrating up and down under wot in the middle of your log there.
either the rings or some valves or both took a hit.

[jeanb]

Thanks I appreciate the info -

I just needed for someone to confirm what I suspected
now I can lay into a service manager - to get it fixed

cheers

[dont_blink]

Cracked ring land. Or the car jumped timing, which doesn't happen usually on chain driven cams.

[jeanb]

well back from the dealership - showed him the hpt scan but
he can't validate that info under GM guideline
- we went for a drive with the GM approved scan tool -

@6000rpm cylinder 3 misfire

His procedures is to check the coils check the plug - to resolve the issue
anything above that goes to Gm rep to validate wether or not to warranty the issue - yet a simple test on cylinder 3 would show the problem
but it's not procedure ... I understood it as like the police going into
a house without a warrant and then tryng to get a conviction...

very disappointing