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So, it looks like Iím another victim of the dreaded P0300. At 54k miles the check engine light came on Thursday. A slight rough idle but nothing that would make me think WTF and was consistently getting 17.8 mpg. Took it in to the dealership, cause I opted for the extended warranty, and sure enough, loss of cylinder pressure in one cylinder. Finally diagnosed today. I hope this is covered under the warranty cause so far Iíve been paying for the rental while theyíve been trying to figure it out. Wonít find out until sometime Monday how this is going to go down from here. I still think GM should cover this but after reading report after report, if itís not a safety issue, then itís not a concern. Oh well, still love my H3 and just venting.
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Yeah, it's an 06. The extended warranty doesn't cover that with only 54k miles?
I still have something like 2 years or 5k miles left of the extended.
I used it 6 months ago then the thermostat was stuck open and a TPM sensor went out. All was covered. Why would they not cover the head?
Ok so this is what I have found. If I understand this correctly, GM should cover this fix 100% right? After all, I do have the extended warranty and the last 6 of my VIN are 234XXX and I do have a 06 with the i5. Are all the planets aligning correctly?
Subject: DTC P0300 And Engine Miss At Idle Due To A Leaking Intake Valve - Replace Cylinder Head With Valves - keywords CEL compression controls excessive high leakage leakdown low MIL misfire P0301 P0302 #PIP3935C - (08/28/2007)
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
On rare occasions, a SES light and P0300 may be experienced due to a single cylinder misfire at idle that may or may not be felt. On vehicles built before the VIN breakpoints above, this may be due to non-uniform intake valve seat wear, preventing the intake valve from sealing properly. Vehicles built after these VIN breakpoints contain harder intake valve seats to prevent intake valve wear and leakage.
Important: The engine misfires described in this PI, which occur as a result of the leaking intake valves mentioned above, will occur at idle only. If the engine misfires occur off of idle, this PI does not apply.
If the SI diagnostics do not isolate a cause for this concern, perform a cylinder leakage test as outlined in the latest version of 07-06-01-011 and in the "Cylinder Leakage Test" procedure from SI. Please document all leakage rates on the repair order.
If a leaking intake valve is found, replace the cylinder head by following the latest version of 06-06-01-017. This bulletin, which contains all of the part numbers that will be needed. The bulletin also contains a revised replacement procedure that no longer requires removal of the oil pan, front cover, water pump, or crankshaft dampener. The cylinder head listed in 06-06-01-017 will come with the valves already installed and it contains harder intake valve seats to prevent future intake valve leakage. When replacing the cylinder head, inspect ALL of the other components from the original cylinder head and transfer them to their original locations on the new cylinder head if there is no problem found with any of them. If there is anything wrong with any of these components, replace them as necessary.
Important: If the vehicle is a 2006 model, install the latest PCM calibrations to complete the repair.
Important: If excessive intake valve leakage is found on a vehicle built after the VIN breakpoints above, repair the vehicle as outlined above and submit a product report by following the latest version of 02-00-89-002. Please include the cylinder leakage rates for each cylinder and any other details that may be useful to engineering
Well, got an update. The service writer didn’t call it in to the warranty company before he left work Friday and still didn’t get it done Sat. I called this morning and talked to a second guy, because the initial service writer won’t be back until tomorrow. I was told that even though GM sent out the service bulletin on the head, they will still try to get the extended warranty company to cover it. So, I’m waiting on their approval and they may also send out an adjuster to inspect the part and try to get GM to cover the repair. All the while, I’m paying for my own rental cause the dealership is out of loaner vehicles. Not a happy camper…
A more recent development, the dealership called and the warranty company is sending out an adjustor. They want to see my service receipts. Hell, I can count 3 times the last year that I paid for someone to change my oil, cause I do that stuff myself. The only reason why I can find one receipt is because I kept it to show that I had the state inspection done at the same time.
Newest update. The warranty inspector came out today, I have no freakn’ clue what he looked at cause my service writer wasn’t there. Called the warranty company and they want to tear the motor down to first determine the point of failure before they decide if they want to repair this. I don’t get it. If its rings, it should be covered, if its valve seats, it should be covered, but in either case, I have never torn down a motor to determine if the loss of cylinder pressure was due to valves, rings or head gasket. I mean come on guys…