missing a cylinder?

[89mulletbird]

I started backfiring the other day under 10+ psi, then after awhile the backfire stopped but it felt like it was only running on 5.

I parked it and didn't look at anything, figured I'd just put new plugs in. When I went to install the new plugs, I saw #1 plug wire was off. I changed the plugs and put everything back together, but it is still running like it's on 5 cylinders. Doesn't feel smooth under load.

My 02's are normal, 800 at WOT.
My plug wires are only a couple thousand miles old, what else should I check out?

 

[Grumpy]

bad cam ??? or just a bad coil pack ... ya have to just start checkin junk

 

[bkoons]

What is driveability and scan readings like at idle & normal driving? Could be a lot of things. For starters, do a compression check to verify mechanical condition. Do all the plugs look the same? Take a look at the valve springs. A flat cam can be checked with enough accuracy to rule out using a dial indicator with a mag base. Could be a bad ignition module or coil pack, you can buy a tester or have it done. Could even be something in the tranny broke. Like Grumpy said, just have to start checking things.

 

[89mulletbird]

status

I checked some things out

All cylinders are 120 - 130psi (whew)
Put new plugs in, ran a few miles, and plug #2 is dark grey, while the rest are still bright white.

Going to check the plug wire and coil pack next.