Skip the auto shop - Our mechanics make house calls

Q: Screeching chirp noise engine - 1991 GMC K2500

asked by on

I replaced a screeching belt in my truck a few weeks ago. It was an old, worn out one. But then my truck started a new screech that was different from the belt screech. I took off the belt, spun the pulleys and the tensioner pulley was grinding, so I replaced that. But it didn’t help. I took the belt off and spun the pulleys again. The alternator was screeching, so I bought a new one. And the engine was still making screeching noises. I put in a new water pump a couple of weeks ago, but that couldn’t be making the noise. This screech is more of a chirp than a screech noise, and it will vary depending upon the RPMs. It goes away sometimes when accelerating the car. I had bought a cheap belt, so I better pick up a better brand. That might possibly help. The belt tension is good and so are the water pump, idler pulley and the alternator that is refurbished. My truck has 271500 miles on it and it’s a 5.7 TBI. Do you have any ideas about what might be making the screeching or rather chirp noise?

A: Hey there. The A/C pulley bearing may be bi...

Hey there. The A/C pulley bearing may be binding causing the chirping. Try spraying each belt one at a time with some water in a spray bottle. The noise will change or go away when the belt that is chirping gets wet. To have this verified, a qualified professional from YourMechanic can come to your car’s location to diagnose the noise and assist with repair.

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

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

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: master cylinder is bad, but does it make a noise going down the road. if so what kind. mine is intermittent

Hello, thank you for writing in. The master cylinder may make some noises, however it is rather unlikely that you are going to hear these fluid sounding noises over the engine noise. Start by adding the differential fluid and take...

Q: Jerking during acceleration and shifting, going uphill

It sounds like you may have been experiencing a misfire. When an engine is misfiring, it can cause the engine to become imbalanced and cause the vibrations that you were experiencing. Another indication of a misfire would be a flashing...

Q: Car chokes after starting

There are two options for the engine for your car. They are both 3.0 v6’s that are vastly different. If you are talking about oil in the spark plug tubes on the DOHC v6, that indicates a bad valve cover...

Related articles

P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the P0052 code means This code is seen when the Engine Control Module (ECM) tries to control the...
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...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.