After it sits it starts hard--lots of cranking, rough start, not all cylinders firing at first then smooths out in 5-10 seconds and runs great. I think the 5-10 second roughness comes from excess fuel being burnt off as there is some fuel smoke coming out of tail pipe. If shut off as soon as it begins to run smooth it will start right up. Whether driven or not, if shut off for more than 5 minutes it will start hard again. So it's not temperature dependent; it's how long it's been sitting. Looked in FAQ's and checked some stuff. Yet to change gas filter. Also, when cranking and not starting, the tach needle just vibrates ever so slightly. Is that normal for the crank position semsor or should it move more? Thanks again. Mario