Skip the auto shop - Our mechanics make house calls

Q: Knocking and rpm revving high

asked by on

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.

A: Hi there. Unfortunately, without being ther...

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.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Car gets hot after 10 minutes

Hello, this is commonly caused by a failing thermostat. When the thermostat fails it will not allow the coolant to circulate causing the engine to get hot. I typically check the temperature of the radiator hoses to see if the...

Q: Car jerking upon acceleration, sluggish engine

You will need to have the ignition and fuel systems checked. The fuel pump and filter should be checked for correct pressure and flow due to clogged filter or pump pressure. The ignition should be checked to see if the...

Q: Knocking noise under hood

Without actually hearing the noise, it is difficult to determine the exact cause of your concern. It could be low oil pressure, valve adjustment, bearing failure, etc. I suggest having a certified technician, like one from YourMechanic, determine the exact...

Related articles

How Long Does a Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.