500 RPM? Oh wow, I never realized that before. My engine pretty much goes down as low as it can before the CEL/oil pressure/check battery lights would come on (the ones that come up when you stall out) but it's almost like the ecu catches itself and bumps it back up. This doesn't happen continuously but every once in a while and is noticeable enough to be annoying. For the gaskets I had a new one for the head/IM connection but I resued the metal gasket between the IM halves. It seemed to be in good enough condition (it still had the little bump-thing) and it wasn't sealed before so I figured it'd still be good to use again - that may have been my problem. Either that or a reassembled everything in a bad order - which could be it. Are you supposed to start at the middle and work your way out to the ends with the bolts/nuts just like with an exhaust manifold? Looking back, I probably should have put the IM halves back together and tightened everything down first, then attach it to the head in the order I explained above. I guess I'll have to try this later when my hands are healed from the first removal...flat_black said:200 rpm? Are you sure you're reading the tach right? The first tick mark, just above 0 rpm is actually 500 rpm, and your engine will stall below that, nearly without fail.
For that matter, the carb cleaner is done to see if there are any vacuum leaks. When you go over the manifold spot that may have a vac leak, the idle should jump up. Really, the gasket should be cleaned off, a new one should either be procured, or just use gasket sealer. Preferably copper or red. I used red personally.