Originally Posted by Saint
Forgot to put the starter return spring back on. Guess that didn't affect much in the big scheme of the engine performance issues, but found it lying on the fender apron.
smile

i wouldn't jump to the conclusion so fast that this issue isn't causing at least some of your symptoms.. you did say this in your first post: "...almost metallic grinding sound..." Could that be the starter gear still engaging the ring gear? Could this sound you hear be interpreted as poor idling?

Did you put the spring back in and run the motor?