Q: Knocking and rpm revving high

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My radiator fan was not coming on. I had a mechanic look at it and he said that he would re-wire the fan to the fuse box so that it could come on as soon as my car would start. But after he did this my car started revving to 4-5 rpm's and it would gain speed but it would take 10-15 seconds. On top of that when I tried to gain speed the engine started knocking after I would try to gain speed. Now when I start the car the engine would knock immediately and now when I push the gas the knocking becomes louder. When I returned the car to the mechanic he said I blew my engine because there was no oil but the day he rapaired my car he checked my oil and there was oil in the car. Do you think it's because there was no oil? Or could it be how he re-wired my car? Again the noise or revving with the high rpm didn't start until after he re-wired my car.

My car has 140472 miles.
My car has an automatic transmission.

Hi there. Unfortunately, without being there to physically inspect the vehicle, it’s hard to pinpoint the precise cause of the engine failure. However, one thing I can say without hesitation is that rewiring your vehicle’s cooling fan was not the correct solution to your radiator fan problem.

Anytime a mechanic assumes that they can bypass an issue by rewiring it or going against the manufacturer’s recommended service manual, they are risking damage to other mechanical components.

My best advice is to contact a different mechanic, perhaps a local ASE certified mechanic, who can inspect the root cause of your radiator fan issue, the unresponsive acceleration, and also any damage that was caused to your engine.

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