I have a 2001 Xterra SE V6 3.3L with about 157k miles.

Recently, the engine has been running rough and the Service Engine Soon light blinks when it gets really rough. It was obvious the engine was misfiring or their was an air/fuel issue.

This is an intermittent problem.

When it went in for service, the tech found that if the ignition wires were misted (moisture) the problem would happen and the engine would run pretty rough and the light would blink.

Ignition wires replaced.

Ran OK for a couple of weeks - not many miles at all - and it started happening again. At one point it was getting very bad and the SES light came on and stayed on. Visited the local AutoZone and asked them to plug in to see if there was a code (light was ON). Came back as Cylinder 1 Misfire.

Made an appointment that day to have it looked at. When I started the truck to drop it off last night, it ran fine with no light. (Only about 1.5 miles at low speeds).

Today, the techs did see the code as it was stored (same thing, Cylinder 1 Misfire) but they could not get the problem to happen again.

Any suggestions?

going through that same thing now.. P0302, Cylinder #2 missfire,.. had it in the garage, new cap, rotor, wires, and new plug in #2. Now, getting code P0300, Random Missfire. I had no replies on my post about it on here, hope you have better luck.