I have a paslode model IM250II 16 ga straight finish nailer that I bought used the gun fan and motor runs whin the trigger is pulled but it does not fire when the tip is pressed no pop no puff nothing I have a new battery and fuel cell in the gun also the motor and fan runs if you just pick it up and pull the trigger is this normal or should the tip be pressed be for fan and motor runs. I thank it may be the spark plug from what I have saw posted on other sights. Thanks I need help!

Fan running when trigger pressed is normal however to make it fire you need to press on the work probe first and the fan should start running, at this point the gas should be injected and pressing the trigger should create the spark to fire the gun, if all works as above but the gun won't fire check the gas, the metering valve on the can should have a yellow ring and when pressing the can nozzle on a hard surface, gas should be released, if not the can either has (a) insufficient gas, (b) the nozzle is not correctly fitted (c) the metering valve is faulty, if the can emits gas the gun will need to be checked for spark and the seals will need checking