I have put about 500 miles on a new to me 245 with great results until driving to work today. It bucked a bit as if the fuel system was doing something funky, like a clogged fuel filter. At stand still the gas had to be fluttered to keep it from stalling. I started it several times through the day to try to blow a potentially clogged injector clear as I just put in some injector cleaner a tank ago. I just replaced the air filter as well which did jiggle the air flow meter (it ran fine for 40 miles hawever). It slowly got better through the day to where now it doesn't seem to hesitate anymore, but it went from a textbook 750 rpm idle to a 1100-1250 idle. I started it numerous times and drove 2- 15 mile trips and every time 1200 rpms. It seems the computer is compensating for something. I have a bit of lite colored smoke if I rev it up which I think is due to some incorrect ratio. I don't have any other clues pointing to head gasket problems, but I'll keep a keen eye tomorrow for the cold start. Any thoughts?