High-pitched noise?

[kinjo1977]

Hearing a couple noises coming from my truck. And not just the notorious engine knock these 4.8s are known for.

One is a high-pitched noise that my truck gives off after running for a while. Think it might be either my exhaust colliding in my y-pipe, or my fuel pump. Anyone else here it?

Second, is a sound that happens when I first start and and take off. Hear it for about a block. Sounds like a whirring/tick coming from the right side of my engine I believe. Thought it was a loose belt but I'm not too familiar with how tight or loose my belt should be. Considered it being the fan clutch but its not.

Hope someone can help.

[RedHeartbeat]

Sounds to me like your smog AIR pump is running. It's supposed to run for a while at startup. It may be running later too but you would just have to check. I am not sure where it is on your truck but I would think that is what your odd noise is you are hearing. It's an electric pump so it whirs as described. The clicking noise you hear may be the check valves inline with the smog plumbing.

[agreif]

high pitched whine could be the alternator, mine does that in the cold weather (it correlates directly with RPM).

Andrew

[andymish]

Sounds to me like your smog AIR pump is running. It's supposed to run for a while at startup. It may be running later too but you would just have to check. I am not sure where it is on your truck but I would think that is what your odd noise is you are hearing. It's an electric pump so it whirs as described. The clicking noise you hear may be the check valves inline with the smog plumbing.

Hey there. I'm kinda curious about that smog air pump you were talking about. Well, my friend seems like experiencing a similar symptom like kinjo on his vehicle and it's kinda confusing why it's doing that. So anyone has the solution to fix this smog air pump and what does it look like? Any information that might be helpful is appreciated.