Hi,

I guess Art and I are thinking the same thing about excessive air, except, he has more experience in manifold gasket changing, as I have only done one!

It’s not hard to do by just loosening the bolts holding it and pulling it back a bit. Just, Be careful not to drop any of the nuts!
If you did take it Further back, you can check the manifold for flatness with a straight edge, as they can warp some over the long haul. I didn’t find much of it from my curiosity of such a thing.
Besides the gasket is suppose to absorb the movement’s but it must give up on some cars eventually?
Seen lots of pictures and not just the same one posted over and over!
(:)

Edit:
Just read about the AMM connector! Very big possibility on that. I thought the Mechanic check that for you but it can be missed if one pin is not tabbed into the socket really good!

Phil