Q: Motor won't rev past 3,000rpm

asked by on July 10, 2017

1995 Mercedes Benz C280 with only 28,000 miles. The motor runs good but it won't go over 3,000rpms. This happens in every gear, including park and neutral. When it reaches 3,000 rpms it bounces like it would if it was redlining. No check engine light so I can't read any code!

My car has 28000 miles.
My car has an automatic transmission.

It sounds like you may have a crankshaft position sensor that may be on the verge of failing. A crankshaft position sensor is an electronic device used to monitor the position or rotational speed of the crankshaft. This information is used by engine management systems to control the fuel injection or the ignition system timing and other engine parameters. When this is faulty or not working properly, this will cause problems with the ignition system and generating spark transmission to the spark plugs resulting in starting problems and other performance issues causing misfires. I would recommend having an expert from YourMechanic come to your location to diagnose and inspect your vehicle.

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