Ze won't start

[boywithamazda]

After replacing some valve stem seals on the front bank of cylinders and putting everything back together, my car won't start. It putters for a few seconds and then dies on first attempt. It does this consistently if you leave it sit for a week and try again but doesn't begin to turn over on sequential tries. It gets spark. The timing marks check out. I replaced the fuel pump on a whim, and it is audible, so that's out. One clue might be that starting is labored sounding, and a spark comes from the solenoid next to the starter when first starting.
Another random clue could be that before changing the stem seals, the speedo would zero out and the radio would short on occasion while driving. The grounds seem to be in check as well however.
My next option seems to be 'professional help' unless anyone has a few ideas?

[RX8SE3P]

This most likely won't help but I couldn't get mine to start at first. It was the PCV vacuum hose from the rear head, that connects to the front head. There's a pipe coming from there and if it's just wide open and not either blocked or routed correctly to the intake pipe, the car will never start properly.

[nightfire]

This is another suggestion out of the blue, but I just had the same problem when I flooded my ZE... got spark and fuel, but wouldn't light up.

It's possible the gas broke down the oil in the cylinders to the point you're not getting compression; check with a compression gauge. If it's <100 it won't start, no matter what. Try airing out the cylinders, cleaning/drying the plugs, and adding some light oil to the cylinders (say 5W20).. 5-10 drops is probably enough. That's what did it for me.