Odd engine noise

[f5journal]

I started a thread on this topic almost 2 years ago. I still have the same noise and thought I would give it another shot.

This noise started at 1500 miles and right after an interstate stop to fill up. Car has 18K now.

I described it before as a slight exhaust leak or ???.

Here are some better terms and info.

This happens on the right side bank only under alot of load and from 2500rpm up.

I do not think it's spark knock

It could be lifters, but it sounds too plastic like and makes no noise at idle or cruise

It is a "chorus" like multiple lifters or exhaust leak might be

If you ever adjusted valve lash on a solid lifter cam, it sounds more like way too much valve lash than anything else I can describe

I have a Janetty tune and have been in contact with him and will be some data logging. His preliminary diagnosis is that there is a mechanical issue with the car that is pulling timing.

I have no LS engine experience. I'm Old school small block Chevy

Could it be the injectors overworking or some weak coils???

Thanks

[Hannibal]

Is it a plastic rattle that sounds worse at lower RPMs and then evens out and maybe even goes away at high RPMs?

[f5journal]

No, it is more plastic than metallic but it simply sounds like 2 bad lifters would do. It is there at engine speed any time you are pushing the car. Not at idle and not when under light load

[Chevrolet Customer Svc]

Originally Posted by f5journal

I started a thread on this topic almost 2 years ago. I still have the same noise and thought I would give it another shot.

This noise started at 1500 miles and right after an interstate stop to fill up. Car has 18K now.

I described it before as a slight exhaust leak or ???.

Here are some better terms and info.

This happens on the right side bank only under alot of load and from 2500rpm up.

I do not think it's spark knock

It could be lifters, but it sounds too plastic like and makes no noise at idle or cruise

It is a "chorus" like multiple lifters or exhaust leak might be

If you ever adjusted valve lash on a solid lifter cam, it sounds more like way too much valve lash than anything else I can describe

I have a Janetty tune and have been in contact with him and will be some data logging. His preliminary diagnosis is that there is a mechanical issue with the car that is pulling timing.

I have no LS engine experience. I'm Old school small block Chevy

Could it be the injectors overworking or some weak coils???

Thanks

Have you had the chance to take it to a dealership for a proper diagnosis? They should be able to diagnose the concern you may be experiencing. Please let us know if you have any questions!

Brandon
Chevrolet Customer Service

[f5journal]

They said it was "normal"

[OregonToFlorida]

Originally Posted by Hannibal

Is it a plastic rattle that sounds worse at lower RPMs and then evens out and maybe even goes away at high RPMs?

I totally have this noise.... I think its my Auto Trans...ive been to the dealer twice to look exhaust and engine ,every thing checked out fine.. Sen ithers with the same trouble on the 12 Rs autos...any help would be awesome

[Greggash]

I have a 2012 1ss M6 and it does the same thing.
it will sound for a moment like its banging on the passenger side, like a diesel.
one day I will find a bad injector. it does not do it all the time.

[Chevrolet Customer Svc]

Originally Posted by Greggash

I have a 2012 1ss M6 and it does the same thing.
it will sound for a moment like its banging on the passenger side, like a diesel.
one day I will find a bad injector. it does not do it all the time.

Have you had the chance to take it into the dealership fora proper diagnosis? Please let us know if you decide to do this!

Brandon
Chevrolet Customer Service