Missing distributor seal possibly causing rough idle at startup?
 

I just installed my cylinder head and every thing that goes with it back on my 1993 Toyota Camry 2.2L engine. Cleaned the IAC, Throttle body out as well as anything that required cleaning. Everything back in place as removed. Now when I go to start it, it starts fine, but the idle is really low and a bit rough to the point of stalling. I let it run a few minutes pressing the gas down a little and then it idles fine. I checked all connectors and everything is in place. One thing I noticed and I am not sure how much of an affect this has. I looked carefully at the distributor cap and did not notice a rubber seal. The only places that there are no gaps between the distributor cap and the distributor unit is where the cap is mounted with screws. Looks like there are gaps all around. I double checked to make sure the cap is correct for the vehicle and it is. I called the dealer and they said yes there is supposed to be a rubber seal. I ordered one ($10.95) so until I receive it I won’t know if moisture could be causing this problem or not.
Any other suggestions would be really helpful.