Tilly started backfiring, poor acceleration and clunking sound. Didn’t sound like a piston rod, push rod, valve as plug pressures 120-150 psi. Sounded like intake or exhaust issue or carb. Heck, on a 39 year old motor, could be anything. None the less , taking apart the engine. Hopefully we don’t have to open the entire engine. Lots of sensors and vacuum hoses. All of which could not be working well. And a manifold bolt was broken in the engine block.
