froggy47

Mine has developed a buzzy/tinny/rattle on pass side about 4 inches back from the exhaust manifold flange. It happens at 2000 rpm in 1st & 2nd, not when stopped & reving.

I don't see any broken welds & I have scrapped a couple of times but nothing major.

The pipe there has some wavy denty stuff going on all the way to the front of the cat.

One tech said he thought that it was double walled to help keep heat in & heat the cat quicker.

Anyone have more info? I have gmpp, maybe I can warr it.

sperkins

I just checked one of my spare H-pipes and it is not double wall.
Have you checked the welds at the crossover flange in front of the cats? Checked all the bolts?

whatcop?

Had the same problem on a C5 before and it was the O2 sensor.

froggy47

Thanks guys, I will have the car up again this week, lol, well it's actually up every week truth be told.



I will bang around some more & put a wrench on some nuts. I am 98% sure it's right near the flange (exhaust header) not back near the cats.

Will inspect welds too with mirror/light.