yet another fluctuating idle

[89 coupe]

i have a 1989 240sx with 118 000km on it. when i start it up everything is running perfectly fine. idle is a bit high, around 1600rpm. once the car is about at running temperature my idle starts to go crazy. revs up to about 2000rpm then drops back down to 1600rpm. creeps back up and drops. it does this about every 2 seconds. i checked my vacuum lines and replaced one that had a crack at the end. i pulled off my idle air control valve and it wasnt all that gunked up with carbon. but i still cleaned it with some intake cleaner. still have the problem. its not insured so i havnt been able to drive it much. but i have taken it around the building a couple times and i havnt noticed anything wrong when driving. this is pretty much what it is like http://www.youtube.com/watch?v...lated any ideas?

[airman86]

i once had a '95 eclipse gs-t with the same problem, and it was the throttle position sensor. it also could have been a combination of the vacuum lines because i fiddled with those when i swapped the TPS for a known-good one.

[NCYankee]

My vote would also be for the TPS, check the harness connector. I used to have idle problems until I packed it with dielectric grease, also had the same problem with a Sentra at the MAF connector.

Why didn't Nissan grease the connectors at the factory like Toyota and Honda? Never had any such problem with my ex's Civic.