Q. My 1995 Lexus SC400 (my weekend car) after sitting for a week and previously running perfectly, feels like it is running on two cylinders.  My mechanic checked the catalytic converter and changed the ignition coil. This made a slight difference, but it still isn’t right. The mechanic advises that the problem may be a “jumped timing belt” but he is not sure.  The dealership advised that if it is a timing belt problem the engine may have valve damage. Please help!

JohnPaul-80-2__1239736084_1429.jpg A. For a car to run properly it needs fuel, spark for ignition and proper engine compression. I would start with a recheck of the basics. This should include fuel volume and pressure tests, ignition system testing and engine/valve timing. There are two ignition coils in this model; the second coil could have also failed.

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