My 05 KQ has been in the shop all last week. Whenever its warmed up it will stall out. Afterwards it difficult to crank. Its like the idle sensor is not working. The shop blames the trouble on my K&N filter allowing dirt to pass. Hell the stock filter did it worse. Anything concrete I make take to them to assist in disproving this excuse? Seems to me if the filter were the trouble it woul dbe a problem in all situations not just once its warmed up.

 

well the kq has fuel injection correct well the o2 sensor might be off...if they think its the dirt from the filter then have them try taking it apart and check it out but my guess would be that the o2 sensor is bad. you said it runs fien when it is cool but when it gets hotter it doesn't work out so the coil and plug should be fine...does the thermostat tie in somehow becuase it could also be a cooling problem...well those are all the things I could think of that you would be able to check yourself without taking the engine apart. good luck.
Brett