Hey all,

I've got a question. Recently I started hearing a buzzing sound coming from the engine and when I popped the hood I was able to narrow the sound down from the area of the PCV Valve. I looked on here and found a possible solution of the throttle cable transmitting the vibration back into the cab. I tried this fix of moving the throttle cable, but to no avail. The noise is only present at idle, but once the engine is under load it either goes away, or I just can't hear it because of engine noise.

Any ideas?

 

Take the PVC valve out and make sure it is clean. If not clean with carbeurator cleaner or replace it. Also make sure the hose and the fitting at the intake manifold are not blocked by carbon.

It is just a 1 way check valve. You should be able to easily blow through it in 1 direction but not the other direction.

PCV valves can make a buzzing sound. If so, you should be able to feel a slight vibration if you put your finger on the PCV valve with the engine running.

 

I went ahead and replaced the Valve. That along with moving the throttle cable out of the way fixed the problem.

Thanks
Jeff

 

I have an 02' Sonoma 4.3L V6. The problem is identical. I came across this on google upon my search so i figured I'd reply. I tried replacing the pvc valve. i blew through the hose and its not plugged or anything. The throttle cable isn't touching it. I can pull the pcv valve out while it is running and it continues to vibrate and make that awful vibration noise in the cab and it's driving me crazy to drive it. Any Ideas??

 

Make sure nothing is touching the PCV hose, that is where my problem was, not the actual PCV valve

 

i think i may have solved the problem. there was nothing touching the pcv valve or hose connecting it. But i've done some research and found that GM has made a couple changes that can stop the rattling. The pcv valves they used to have like mine have a tumbler or bearing inside which rattles even if you just shake it. They cam out with a new one which is a fixed orifice style with nothing inside it but the hole in the bottom is .100 of an inch or something (a.k.a very small) which controls the air flow. I'm going to try that and maybe the rattling (that's driving me crazy) will go away. opinion??

 

PCV valves are specificly designed for each vehicle application. If you do not use the correct PCV you may end up with idle and or fuel economy issues. The PCV is a calibrated vacuum leak so to much or to little air flow thorugh the PCV is not optimum.

 

hockey tape to the rescue. wrapping it in tape works good.

 

where do i find the right ones. the one im using is purolator from advanced auto and mine buzzes like crap and i idle slightly weak. im hoping there is no vac leak or excessive blow by. i would not know what to do in that situation.