New 400i new concerns

Well new battery in, solid terminals, installed a few new vacuum lines. (Stupid ca extra stuff) and re-installed right conveyor. Car starts right up as it has always done.

Concern 1. But when revving car it seems to misfire, bog down. but when it was warm, like a full 10/15 minutes of idling and playing with accelerator looking for a problem, it started running strong. But idle was bouncing back and forth 750-1000rpm. And if I increase revs at idle and back off car wants to die unless I keep it going. Car has only few hundred miles in last few years so maybe bad gas, moisture, clogged injectors. Thinking of a tank of new gas and fuel additive to check and clean as when started car today it did the same bogging down at first. Suggestions?

Concern 2. Speaking of right side. There is a metal flange below the head, head gasket? I have cleaned off fluid from it a couple of times. Accumulates on the rim but seems to be damp all the way up to engine as well. It feels like a light lubricant. It’s not like my oil or antifreeze or fuel. A mixture? Any ideas? Left side Completely dry. Worried it’s not good.

Thanks as always. New car fears setting in.

 

thanks Ken. Similar thoughts on #1 but am concerned of electrical and vacuum as a secondary. I keep looking around. As far as #2 goes I know the hydrolic suspension has been swapped out. So not sure if that so trying to determine where the fluid could also be coming from? Do you know if the head gasket sits above that heat shield maybe seeping from there? Or do you know if there’s anywhere fuel could be coming from to get on that heat shield? I just don’t see anything specific.