idle problem

[Jason Nicholson]

Ok, I have a 99SE-L w/ JWT S3 cams & ecu, cai, etc.  Over the 2-3 couple of months my engine idle would occassionally have trouble settling down.  The idle would just stay at 1500rpm, even when the engine has warmed up.  When this would happen I'd just turn the car off and restart it, which usually solved the problem on the first try.  The past few days, though, the problem has been much more persistent.  Any ideas?

As a side note, the ecu is from a '97SE-R and all the required conversions were made, including the rear O2 sensor.  However, the service engine light went on a little over a month ago when this O2 sensor went dead.  I still haven't replaced it because I'm waiting for the replacement from Mossy Nissan.  Could this be a factor?

Thanks for any help,

Jason