2016 Chevy Silverado still has rough idle even after camshaft replacement

YousefR2007
Wed, 17 May 2023 16:19:28 +0000
Maintenance/Repairs

Hello,

Looking for some input here. I have a 2016 Chevy Silverado 1500 LS, 4.3L LV3 V6. It was rough and loud when it idled, so I tore down the engine and found two of the camshaft lobes had been gouged as well as two of the lifters. I replaced the camshaft, the lifters, lifter guides, rocker arms, pushrods, valve springs, valves, valve seals, all the gaskets needed to get to the camshaft (head gaskets, valve cover gaskets, water pump gaskets), and I changed the spark plugs and the wires. I went through and torqued everything to spec, and in the proper torque sequence (according to the Haynes manual) for the head bolts and the oil pan bolts and timing chain cover bolts. I put the timing chains back properly also. For the initial startup after rebuild, I had the spark plugs out and took out the fuses for the fuel injectors and the fuel pump and turned the key to build oil pressure. Then i installed the spark plugs and wires, put the fuses back, and then I went to start the truck for the first time. It started up, but now it still sounds rough!!! It is a little better than before changing the cam shaft, but still rough nonetheless. See the video at the link below.

It may be a longshot to be able to diagnose from just listening to a video. There is some squeaking from the belt, which I’ll figure out, but why is the engine still sounding and running so rough on idle? If I push on the gas a little a smooths out, but on idle it is rough.

Should I be looking at replacing the fuel rails, fuel filter, fuel pump?

If you listen to the video, seems like a sucking sound almost. Is this the vacuum pump?

Any thoughts would be appreciated.

https://youtu.be/fXSnulQTTmA

9 posts - 7 participants