OK, thinking caps, please.
The car sounds great and is strong on acceleration, but it is like there is a slight, and I mean almost not audible, snap/pop on high rev deceleration. And it does not occur such that it is rev related. It might be some kind of post-ignition detonation in the exhaust system.
I had the valves lashed 400 miles ago, and there is no obvious sound of tapping or leaks. I know burned, bent valve sounds, and the engine would not perform like it is with a valve or a burned piston. I know those effects.
I have good hoses to the decel valve, which is tested and working. I have no exhaust leaks that I can hear. It idles perfectly.
This is a Dansk correct 2.0L muffler. Nearly new. Finished in Wurth Zinc Silver.
My detailer and I took off the muffler and reinstalled it perfectly to fix the detent bolt on the speedo. We used new bolts on the headers/muffler, and the gaskets are not new but almost new and not even worn. I checked all the head exhaust bolts. No sign of a leak. No loose anything. Shook the pipes to see if one was loose.
I am thinking it could be tin inside the Dansk???
Would once-used almost new exhaust gaskets cause a minor leak? They were bolted to correct torque specs.
Also does not seem like the heat shield is loose above the Dansk.
Any ideas?
Anything?
Thanks!
John
avidfanjpl