Hi All, Thanks a lot for helping me out when I installed my new dual downpipe exhaust. She sounds fantastic now. Far better than the previous rattle
- leak combo. And thanks again for helping me out with her second exhaust leak. It turned out to be an install error on my part. I put the exhaust manifold gaskets all on in the same orientation, the two on the left are supposed to be opposite the two on the right. (On the brighter side, I'm getting good at taking the manifolds off!)
While I had the manifolds off, I checked out the valves. Three of the exhaust valves looked gray and dull while the last was black and glistening (looked wet to me). What might cause this? and is it something I need to be concerned about? I plan on keeping the car for ~two more years.
Also, we're approaching winter and every year when the temperature gets low like this her idle starts getting unstable on a cold start and improves (although not great) once she's warmed up. It'll hang around 900-1000 rpms then slowly drop to almost stall (200?) then jumps back up, or she just stalls. I read that vacuum lines can affect this, having just removed the intake twice, I know the vacuum lines are in good shape. The only questionable one is on the rear side of the intake. It also sounds like the idle stabilizer valve could be an issue, how can I test this?
This almost stall situation can be replicated. If I rev the engine up
However, If I give her a slight bump then take my foot off the gas, the idle won't catch and she may stall.
thanks, Matt