I've just done a partial tune-up on my 88 Formula, and won't be able to replace the distributor until tomorrow, if it arrives. It's running pretty rough after changing plugs, distributor cap, and wires. As it stands I think the timing is pretty bad, and I want to make sure the sound I'm hearing is in fact a timing issue. I have loss of power, and get an occasional near-stall with a sound that is something like a cork popping out of a bottle when I release the clutch at lower rpm. It's a new sound to me, so I defer to those with more experience.

Its possible that an exhaust valve is completely open when the spark plug fires, which will make a good 'pop'.....but I never thought of a cork when I heard it.

check for a crossed wire. if it run half way decent before the tune up chances you cross wired it. Trace your #1 plug wire to the cap then run your firing order to each, if you got it cross wired your firing order wont come out right.

Checked and double checked for cross wires. That's out. Would the exhaust valve make sense if it's doing it in first/reverse and less than 2000rpm only? I feel the engine has too much momentum behind it in the higher gears to really do it. It bogs, nearly stalls, and *pops*.

It had a slight hunting idle before tune-up work began, which is completely gone now. Maybe it just isn't firing in one cylinder? It's pretty rough. The distributor is in really rough shape. Lots of corrosion.

[This message has been edited by Xuin39 (edited 02-26-2014).]

If the timing is way out it will pop a little. Make sure the distributor is set at TDC, that should be close enough to get it running then set the timing according to the decal inside your hatch. Pop should go away and it should purr like a kitten!

The corrosion does not seem to matter, but if the pickup coil is trash, It may be firing only one in about 5 chances.....when that happens, fumes get down in the exhaust manifold before they are ignited......and you get a pop.

It certainly smells like gas fumes. I think I'll hold off until I get that new distributor to set the timing. I'll probably pick up a timing light to ease things along. I was worried it could be something outside of the timing, as I tried not to do anything to change it. You should really see the inside of the old cap...the points are nearly gone haha. Teaches me to neglect tune ups.

Pickup coil kind of makes sense I think, given the fumes and back fire/pop

[This message has been edited by Xuin39 (edited 02-26-2014).]