I have a 1990 Honda Accord that I purchased new. It has 120K. Last
summer it started to miss under load (going up a hill for example). It
only occured occassionally - it was not consistent. About 2 months
ago, I was driving home from a friend's home about 45 minutes away by
the freeway. It ran fine on the way down, but it started to miss so
bad on the way home that I thought it might fall apart. I limped it
home and wondered. Driving around town it is fine. It starts and idles
fine too.

The funny thing about this situation is that a couple of months back I
noticed one of the plugs wires was not completely covering the hole of
the spark plug. The side was curled under somewhat. Not a huge amount,
but it did not seal it. I fixed it and pressed it back down correctly
- I don't know why I had not noticed this before. This was the spark
plug furthest to the driver's side. The car has not had a tuneup since
1997 when it had just under 73K. At that time I had the timing belt
replaced as well.

This last weekend, I replaced all the plugs (Bosch+4), plug wires, cap
and rotor. The car runs somewhat better, but still misses under load -
just not so bad. When I removed the spark plug cap from the plug
furthest to the driver's side, I noticed that the walls inside were
extremely dirty - like a fine dust. The plug was tight. But before I
removed it, I used an air compressor to blow out the dust. It came out
in clouds. I don't understand why it was so dirty. All 3 remaining
plug cylinders (correct word?) were clean as new!

I am thinking now that maybe it should have the timing checked, but
I'm not sure what else could be going on. Does anyone have any
thoughts on what I could look at next? I am thinking that I should
also have the timing belt replaced too as it's been 10 years - even
though the mileage is only about 37K since it was last changed.

I appreciate any comments or thoughts!

Thanks,
Dave