Not Ranked
I hate to add a "this or "that" but I had a similar problem with a Corvette a number of years ago. Same issue on one cylinder. All the symptoms of what you had and I checked all the things you that you have looked at.
Within the valve spring retainer--which is not visible to the naked eye--the top two lands of the spring were broken. The valve opened fine when doing a remote starter crank. I diagnosed it by a wire pull with a tach. The car didn't miss that bad until under a load and at higher RPMs. Compression was there, wires and plugs checked out, just about drove me nuts. Filled the cylinder with air and removed the retainer to examine the valve spring (thought it might be a soft spring) and found it.
Good luck
|