02 Accord 4door EX 6cylinder. I changed the timing belt and water pump, installed new plugs, new PVC valve, new air filter and changed the oil and filter. Buttoned it back up, it started immediately and sounded great. After it warmed up, the idle would pulse up and down with the AC compressor cycles, sometimes stalling. Never did before the work. It also set a 1399 (random misfire) code on the code reader. I reinstalled the old plugs, cleared the code, and it seemed better for a short time. Then it started again, only when the AC unit is cycling. If I turn off the unit, it runs like a champ. Also no return of the code............yet. (130 mi.) Any help will be greatly appreciated. Thanks!

Recheck that the timing marks on the sprockets are per the repair manual.
And a WAG: Also check the Idle air valve connector (unplug it and plug it back in)...

Do a Crank Position Relearn (search, it's a common problem anytime you screw with the crank position sensor.)

Double check the timing, not just with the marks on the covers, but with the marks cast into the heads.

Do a Crank Position Relearn (search, it's a common problem anytime you screw with the crank position sensor.)

Double check the timing, not just with the marks on the covers, but with the marks cast into the heads.

Thanks for the info. The crank position relearn sounds like a real possibilty since I removed the crank position sensor to clean it after it was drenched with coolant when I removed the water pump. I assume this is a dealer fix unless one has access to a Honda code machine. I am fairly certain the timing gears were lined up with the casting marks. Other than the idle problem it seems to run perfect. I really appreciate the info.

Recheck that the timing marks on the sprockets are per the repair manual.
And a WAG: Also check the Idle air valve connector (unplug it and plug it back in)...

Thanks for the info. I think the timing marks were perfect, but I am going to check the IAV. I appreciate the reply.

Thanks all. I finally took it to the local dealer and discovered that I was off by one tooth one the right side cam gear. Just enough to cause a problem. I took it home and repeated the whole job and it ran perfect. We just returned home from Washington DC (1100 miles)with no problems. My hands will take awhile to heal though...............lol

FF1953:

My FIRST guess was that you were off ONE tooth on either gear. That will goof it up, every time. Glad you're rolling again! :thmsup: :)