Kyle Page

So my 2004 Chevy Silverado 1500 z71 5.3L 4l60e has this chirping sound under the hood. Only happens when I’m giving it gas. Will stop as soon as I let off. I’ve replaced the main belt tensioner pulley. Hand spun all the rest and they are all smooth and make no sound. Also replaced the ac tensioner pulley and belt. Few weeks ago before this sound started. The truck started having issues starting. Turned out to be ignition switch. And replace starter cause of all the cranking. And battery. Then it would start and die immediately a couple days later. Turned out had multiple bad plugs. So replaced all plugs. But not wires cause they only have 8k miles on them. Got it all fixed then the chirping sound started. At first it was only after first starting it and would go away after a few minutes driving. But last week in the middle of driving down the road it just started chirping. This time it didn’t go away. And soon after I plugged my code reader in and it threw codes for all 4 o2 sensors. But they have been bad for a couple months. I have new ones just not putting on till I figure this out. And also threw a p0306 cylinder 6 misfire. So I took the injector, coil pack, plug wire and spark plug and put them in bank 1 so cylinders 1,3,5,7 to isolate what caused the problem. Cleared all the codes and went for a drive. As soon as I hit the gas just enough to get moving the chirping sound starts back. Continues to chirp until I let off the gas. Drove it a few more times. And only codes to come back are for the o2 sensors. No misfire codes or anything yet. I don’t drive far cause I don’t want to take a chance on it being something seriously bad. I thought about it being something internal but in my experience something like that makes sounds regardless if it’s under load or not. But if I’m wrong please correct me. I’ll post a video tomorrow of the sound for help figuring it out. Thank you!!

dpieroni3

you can verify if it's the serpentine belt by removing it and see if the chirp noise goes away. If it does then reinstall it and get some one to run it to get the noise and try moving the belt forward and back slightly on the water pump pulley with a prybar (be careful) and see if the noise goes away. If it goes away in one direction then you can reposition the power steering pulley on the pump in the same direction. Have see this alot over the years. The power steering pump pulley out of alignment causes the serpentine belt to chirp on the crank pulley. Just a thought and hope it's helpful.

Rednucleus

Does the chirp change frequency as the motor revs faster? Does it only happen while driving, or can you hear it in park revving engine?

Kyle Page

only happens while driving. Gets louder the higher the rpm’s are. You can’t hear it in park revving it. Only in drive driving. https://m.youtube.com/watch?v=GQ2RbnXFjYQ&t=2s here is my video of the sound. It sounds like a belt but it feels like something different. Also to me it sounds like it’s coming from the right side of the engine. Maybe it is the belt and I’ve overlooked everything lol but idk. I know the truck and I just feel like it’s not that easy lol

Kyle Page

I took the belts off and ran it without it and the sound is still there when I accelerate. So it’s not the belts or pulleys causing the sound. Any ideas on what to do next

dpieroni3

I the noise definitely from the engine, or could you have a bad u-joint ?