I have an rpm stumbling issue. I also have a 2 year old exhaust leak (courtasy of slip-on collectors ).

Rpms stumble when I start the car, not everytime but most of the time. Once I've been driving about 5-10 miles it clears up. This has been happening for the last 2 weeks now.

My A/c has started to fade in and out, sometimes it's fine, other times it pushes warm air out. This has been a 3-4 week issue.

My power steering went out last week, replaced the belt tensioner and belt. That seened to work until today, the steering went out for 10 minutes, then started working fine again. Was this possibly from rain? It's never happed from rain in the 4 years I've had the car.


My attack plan to solve this rpm problem since I hhave no clue what this is....
-replace O2 sensor and fix exhaust leak by welding the collectors to the headers.
-replace IAT
-replace coil
-replace opti. I was planning on doing a cam swap as soon as I find the problem, but if I have to replace the opti I'd want to do the swap at the same time. However, if the new opti doesn't work I feel I'll only compound the issue with a new cam, tuning, etc. Any thoughts?

Wow, I'll stop here. Please help.

 

How are the plugs and wires? The plugs could need replacing and/or the plug wires could be burnt/arcing. You can see the wires arcing if you watch the wires in the dark w/engine running.