We tried everything- finally towed it to the dealership. They called to say they didn't know what the problem was but knew there was no compression in one of the cylinders. Basically, they explained that I would have to pay $600 for them to pull the head off Monday. The technician explained that it was probably a valve and the cost would be around $3500. I am in complete shock. What should I do? Someone told me that compression problems may be related to timing.