Why is there a screech sound when I turn the key to start my car?

Asked by Nov 24, 2012 at 10:40 AM

Question type: General

This just happened the past 3 times, and the car does start and run fine, but I would like to know the cause and if there's a simple fix?

7 Answers

Do you mean after it starts? If so, it may be the serpentine belt (if that is what your car has, you do not say what car, year, anything) screeching from the load of the alternator re-charging the battery and slipping. An alternator really does put quite a load on the belt when operation at maximum. Check belt tension. And there are products that spray on to help give the belt 'traction', I personally don't like most spray-on stuff for anything, but this is an exception. The stuff works

4 people found this helpful.

premier123 has a good point there

4 people found this helpful.

it is the belt that makes that noise on start up,squirt it with some WD-40 and it should go away...

4 people found this helpful.

Yeah, but Jack if it's already slipping, and has proper tension WD40 would just make it slip more. Or not? That just sounds like putting grease on brake rotors, sure, they will stop making noise but............****Jack*** correct me if I am wrong here. Maybe the rubber with WD40 on it is different than say metal on metal

3 people found this helpful.

If this is when you turn the key, before it starts, there are two possible causes: A defective Bendix drive, which means a new starter motor, or a damaged ring gear on the flywheel, which means a new flywheel. If it is after the car starts, I would change the serpentine belt, but also check the tensioner and idler pulleys and make sure they are both good. WD-40 will possibly quiet things down temporarily, but won't fix the problem.

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@DavidH25,the WD-40 simply cleans away any of the glazing that might be on the belt and gives it a clean surface to grab the pulleys with,it is only a temporary fix to see if it is the belt making the noise.Sometimes a clutch fan can cause "squeeling"or even a worn pulley but they tend to squeal constantly rather than just on start-up...and yes you would need to replace the belt and check tension on the idler pulley to see if it is the problem too.

2 people found this helpful.

Mine is doing this only when the key is being turned over no belts squelling...

3 people found this helpful.

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