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Q: Car sometimes give me acceleration and power issues. Engine power reduced message and engine light appear intermittently.

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I sometimes experience sluggish acceleration followed by what feels like the car bucking and then "engine power reduced" message appears on the dashboard along with a solid check engine light. The car then feels like it's going to stall so I immediately pull it to the side of the road and turn it off. About five minutes later I turn it on and it drives fine but the engine light stays on. Apparently though, the engine light eventually goes away after a handful of ignition rotations and I can't seem to figure out why this keeps happening.

The first time I took it to my personal mechanic to run a diagnostic test the code came up for the pedal sensor so I got that replaced and thought all was well. However, it just recently happened again and diagnostic tests at both the dealership and where I had the pedal sensor replaced reveal no "error codes" to identify any problem. Why would this continue to happen if diagnostics reveal everything is fine and how should I go about correcting this?

My car has 948000 miles.
My car has an automatic transmission.

It is possible that your vehicle’s PCM has failed. This is somewhat of a common problem amongst many GM vehicles. If the computer has failed, this could be one of the reasons that no trouble codes are appearing and the fact that the problem is intermittent. It is possible that the computer is somehow getting overheated and by stopping the vehicle for a short period of time, the PCM cools down allowing the vehicle to run again. I would recommend having your PCM tested for proper function by a certified technician with experience in computer diagnostics.

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