horchoha wrote:
rx7locost wrote:
I was thinking a bad lobe on the cam or poor valve adjustment might prevent fuel from entering. But the compression would have shown that, no?
A worn cam lobe can still show good compression, (even if the valve opens just a hair, it would allow enough air into the cylinder to be compressed at cranking speed). Process of elimination,the valve cover needs to be pulled and lobes, rockers, push rods inspected.
I also tend to think the cam may be suspect. Lack of compressed fuel/air mixture will give no spark. If the motor sat for a long time, stuck valves or worn cam lobe can cause all kinds of problems. A leaking head gasket that is not allowing water in but allows loss of compression can also be a suspect.
My 1st car (55 Chevy V8) at 16 had a constant miss. Thanks to an old, retired mechanic neighbor testing the compression on # 2 & 4 cylinders showed low compression, but not extremely low. We popped the head off and discovered a blown head gasket between 2 & 4 cly. It had caused a groove to wear into not only the head but in the block. Ultimately, had to replace the motor.