1993 j30 idle and cold start up issues need help please!

[infinitiboyj30]

when the engine is warmed up and im driving and go to a full stop the idle drops to 600rpm and stays there then when i put it in park it goes up to like 780ish and i think this is not normal but people on the forums says thats how the car is?

when i turn the heat on the idle goes up for a while to like 800rpm and then drops back to 570-600rpm and then in a few min it will jump back up to like 800rpm?

now when i go to cold start my car it starts up right away and idles high which is normal but then the idle will drop all the way to like zero and shake alot and then it will go back up and stay there? sometimes it will drop so low and die out on me....i think something is clogged here what do u think? should i clean my iacv and see what happens and my throttle bodies?

i replaced 2 pcvs,fuel filter,air filter,changed the oil and filter,new duralast gold battery,spark plugs,replaced 2 fuel injectors and had the rest cleaned,cleaned the maf sensor with crc maf sensor cleaner,threw in a full bottle of redline si-1 fuel system cleaner on a near empty tank and filled up,and it still is doin the same thing
Modified by infinitiboyj30 at 5:53 PM 3/8/2009

[driverdriver]

Are you tripping and codes? Have you checked the ECU for codes?

[infinitiboyj30]

Are you tripping and codes? Have you checked the ECU for codes?

there are no lights on though so i cant pull the codes.

[GerryO]

when i turn the heat on the idle goes up for a while to like 800rpm and then drops back to 570-600rpm and then in a few min it will jump back up to like 800rpm?

now when i go to cold start my car it starts up right away and idles high which is normal but then the idle will drop all the way to like zero and shake alot and then it will go back up and stay there? sometimes it will drop so low and die out on me....i think something is clogged here what do u think? should i clean my iacv and see what happens and my throttle bodies?

Modified by infinitiboyj30 at 5:53 PM 3/8/2009

Everything sounds very normal, aside from the fact that the engine when fully warm will not idle smoothly at the programmed ECM rpm.

Dirty throttle bodies, dirty/faulty AAC/IAC valves, dirty air filter, mis-adjusted TPS, incorrect timing?

Have you read the Trouble Diagnoses section of the FSM? They mention a Dirty IAS (Idle Adjustment Screw) or Throttle Body clogging under #47 (Engine Stalls after Decelerating), along with performing a Power Balance Test, to check for a bad injector, coil pack or cylinder.

[infinitiboyj30]

Everything sounds very normal, aside from the fact that the engine when fully warm will not idle smoothly at the programmed ECM rpm.

Dirty throttle bodies, dirty/faulty AAC/IAC valves, dirty air filter, mis-adjusted TPS, incorrect timing?

Have you read the Trouble Diagnoses section of the FSM? They mention a Dirty IAS (Idle Adjustment Screw) or Throttle Body clogging under #47 (Engine Stalls after Decelerating), along with performing a Power Balance Test, to check for a bad injector, coil pack or cylinder.

well i know its def not my air filter or maf sensor cause i just put a brand new air filter in and i cleaned the maf sensor with crc maf sensor cleaner....but im gonna try to clean the throttle bodies and aac.iav valves and see what happens...