Q: Low compression cylinder 2 and 4

asked by on July 21, 2017

Hi, I got into an accident in my car listed above it is the SHO model. My car ran perfectly before my accident. I thought I just needed a new rim and to replace the inner fender well and bottom splash guard. I was crossing railroad tracks and my wheel went off of the cement panel and slammed down extremely hard. After the rim was fixed, I picked up my car and drove it to the grocery store. I came out and my car would not start, battery was drained. We had to try to jump my car for over and hour and finally it started. Then I get home and notice my car is leaking some sort of oil and running super rough and bouncing when the car was almost at a stop. I took the car to a separate mechanic and he told me my car was leaking from the power train unit (PTU) and the force from my accident definitely could have caused that to leak. He put a diagnostic tester on the engine and apparently my car now has super low compression in cylinder two and four.

My car has 58000 miles.
My car has an automatic transmission.

If the compression is below the minimum specified in the service manual, the mechanical (or head gasket) issue causing that will have to be resolved. Either the cylinders (2 and 4) are leaking through the head gasket, the valves or the rings. The compression test should be repeated, by the way, just in case the results are in error. At this point, if you want a diagnostic and a repair plan to get the car back in working order, please use YourMechanic’s service request page and the responding certified mechanic will address all of your concerns and let you know of your repair options and costs. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

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