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Q: engine sound

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When i accelerate on pass the 40mph, the car engine makes a weird grinding sound and when i let go of the gas it stops, when i keep it steady the car makes not grinding sound, only when i accelerate

My car has 150000 miles.
My car has an automatic transmission.

This sounds like the engine is having pre-ignition. There can be more than a few caused for the problem. The engine pings from the engine running lean or the ignition timing being advanced. The first thing to check would be to scan the computer to see if any codes are present and diagnose and fix them as needed. If there are no codes to be addressed then look at the mass air sensor reading with the key on and the engine off, to see what the barometer reading is. If the sensor is not reading the correct altitude then replace the sensor. When this sensor is not reading correctly the computer may think you are above 10000 ft in altitude and will not set a code or give enough fuel and pings.

If you need some assistance with this, contact a certified mechanic who can perform the necessary checks to accurately diagnose the sound of your engine and make the necessary repairs to your vehicle.

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