1990 C2 Idle issue
 

Typically i fire up my car from the window in the garage to warm up. after about a minute it starts to idle rough. yesterday for the first time an enormous amount of blueish gray smoke started to exit the exhaust at idle, a couple of revs and a trip done the street cleared it out. Any ideas on the problem. Also between 4000-5000 Rpm there's a hesitation on acceleration? Thanks Jeff:confused:

On 964s, if they are simply started and then not driven and the process is repeated a few times, some blue smoke may be present once it heats up.