Okay...ive seen several posts on the idle surge/high idle issue but none seem to follow up or dont solve my problem so trying to get a little help. I have a 99 eclipse(no turbo yet) rebuilt engine (bored .02 over) with ~100000 on rebuilt engine. a couple months ago it started idling high and surging in the 1500-2000rpm range. at start up it goes to ~3000rpm. It has now started jumping up to ~3000-4000rpm on occasion while either stopped or driving, let out on the clutch and the car will drive itself, its very erratic and doesnt do it all the time. Pulled the codes and its throwing a TPS and all cylinders are misfiring. it will also diesel when i cut the ignition sometimes. i have checked for vac leaks and found none. replaced the TPS, IAT sensor, ISC motor, and the coolant temp sensor. i have also checked egr, and ignition coil. Not sure what else to do.

well if your throwing a code for TPS, there obviously seems to be a problem with the tps. That or a bad vacuum leak somewhere.
also are you sure the throttle body is closing completely?

also check your 02 sensor

that was my problem with erratic idle

i checked for vaccuum leaks and couldnt find anything so if its there i cant find it. Would a vac leak come and go erratically? Seems like if that were it it would be bad all the time. i swapped the TPS and it still had the problem, that one definately confuses me. I checked to make sure the TB was closing all the way it was fine. i havent checked the O2 sensors yet. I will try that tomorrow. any idea what would cause the cylinder misfires?

maybe your plugs wires are grounding somewhere
have you tried looking under the hood while the car is running in pitch dark

if your plug wires are bad you can see arc going from the wire to the body/engine

or you can run your fingers over the wires while it is running
dont suggest it but it will definetly tell you if your wires are arcing



i get the cylinder misfire cel everytime i activate my stutter box

like duh
stupid car

Read this, shows you how to check your TPS and MAP sensors.

http://www.allpar.com/fix/idling-repair.html