spina74

Starting from the passenger side: 130psi 130psi 150psi 95psi

i found out its the vac tank bypass mod

Zander916

Oooooo.... sorry man. It doesn't look good.

I'm not trying to say what it is. It could be a valve problem... could be a lot of things.

But I had from passenger side: 146, 126, 138, 30

NEW pictures of OLD pistons... so there's some rust.
What my 126 piston looked like


What my 30 piston looked like


You'll have to do some digging.

SSlobalt

Yeah, if it's not carbon build-up on the valves, that's the dead cylinder Tom was talking about. Is your misfire code for that cylinder?

spina74

No misfire code at all. The cel goes away after the engine is under load again and theres nothing in the cel history

spina74

I have an appointment at chevy on monday, thank god im still under the powertrain warranty.

SSlobalt

I suggest you remove absolutely every modification you have. If you are tuned, you are likely screwed.

spina74

Nope untuned

Iam Broke

iTrader: (10)

Sounds like #4 **** the bed. Keep us posted. Only chance you have is to go back to stock & write entire the stock tune if it isn't. Even then there are signs you were tuned in the BCM/ECM data & history. They can tell you just flashed or reset the ECU as none of the emission tests will show ready.

GM is currently requiring a deep drilldown into the ECU on many 'tuner' cars like the LNF on an engine failure.

If you log all 4 cyl misfires in HP Tuners, you will see the misfiring cyl count go up like crazy on the dead one at idle when the CEL flashes. Sometimes #2 will show as #4 and #1 will show as #3 but you will see the most dominant one.

spina74

all i can hope is the previous owner didnt tune it, but if they do find a reason to say no, im trading it in.

Zander916

My number two was found with the broken piece still in place but floating around in there.

When mine went, it also ran a little funny at idle about 1-2 weeks prior to it just giving out. First I started killing it while leaving from a stop. I thought that was rather unusual at the time. Looking back it now makes sense that it was low on compression for a few weeks before and just didn't have much off idle or low rpm torque. It seemed to run fine otherwise and no codes set which is why I didn't pay much attention.

Good luck! I hope they warranty it for you.

SSlobalt

Then put all your stock parts back on, down to the IC. If you don't have the stock parts, expect some grief from the dealership. I'm not saying I guarantee it, but dealerships are a toss-up.

spina74

I have everything to go back to stock, and since my friend has an HHR SS I got lucky that he still has his stock IC which I'll be borrowing, since mine came with the aftermarket one.

spina74

Well got a call from chevy, the cylinder head needs to be replaced(kinda was hoping I would be getting a new engine haha), its getting covered under the powertrain....now just to get them to let my rental be a corvette