Weird ideling problem

[lv2plyguitar 172]

I have a problem with my engine that maybe you can help me solve.  When I start up my engine cold it idles at 2000 rpm.  Sometimes, not all the time, the idle kicks up to 2600 after flying around and then landing.  It will do that for a while and then suddenly drop back to 2000 rpm.  I noticed on my talkeetna trip that the front cylinder was running 50 to 60 hotter than the rear. 

 

What are your suggestions to track this down.  It is hard to figure out because it is random.  Some ideas I have are a cable not letting the carb slide all the way down.  Cable on the adjustable mixture sticking and not letting the slide all the way down.  Sucking air on one cylinder (seems like this would be constant and not just every now and then if that were the problem). 

 

 

 

 

[Russ. 7]

Check the carb. boots for cracks.

[akflyer 1427]

Carb boot for cracks, and make sure that you did not twist the barrel when you slipped it back in the carb.  I had a guy messing with the inflight on his and when he put the barrel back in the carb he twisted it so the inflight was wrapped around the main cable and it caused all kinds of problems.  The only other thing would be that the cable is hanging up and the carbs are not opening and closing correctly.