Q: My 2008 Pontiac G8 GT has a collapsed lifter, and i want to have contact with a mechanic experienced in rebuilding Gen IV LS motor

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My car has what I believe to be a collapsed lifter on the exhaust valve of the #2 cylinder. The motor will start, but runs like HOLY HELL, banging loudly on the passenger side, shaking back and forth, etc. I pulled the passenger side valve cover and found the first rocker arm to have almost an inch of clearance, so it was easily flopping around with my finger. I removed that lifter, removed the push rod. It was straight with no mushrooming or marks of any kind. I know my motor (L76) has GM's Active Fuel Management, but the #2 cylinder is NOT an AFM cylinder, and has a regular LS7 lifter. I assume my camshaft is toast as well, so I'm leaning towards disabling the AFM system, installing a "normal" cam w./all new lifters. I know of no one experienced in rebuilding Gen IV LS motors in the Bay Area, and I don't wanna be anyone's guinea pig. Can I get some referrals for mechanics in my area with this kind of experience and can help with my car?

My car has 97500 miles.
My car has an automatic transmission.

California guidelines prohibit the modification of the camshaft that you are contemplating. Consequently, anyone in California who is actually a knowledgeable engine specialist is not going to do this kind of work because it would be flat out illegal. There is also a practical issue that if the modification is performed, you might run into issues with the engine computer. What you need is a repair and careful inspection to determine what, if anything, has been damaged beyond the lifter. Also, the reason for the lifter failure has to be determined. Any of YourMechanic’s engine specialists can assist you. What I would recommend is that you use the service request page and clearly note that you are looking for a certified specialist (ASE) in engine mechanical components. The responding certified mechanic will get you fixed up and address any and all concerns that you have. If you have further questions, do not hesitate to re-contact YourMechanic because we want you to make the most of your repair dollars and help you to get the best possible results.

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