RB20 idle problems...

[slowrb20]

i was just driving my car on a fairly cold day today.... i stopped at a red light pushed the clutch in and it becgan to idle surge. i dont have a tach but i would say about 1grand all the way up to 2-2500. i intstantly thought maf sensor. so i went home started the car up and un plugged it but it still idle surged. i was told when a sensor goes bad if you unplug it the problem will go away if thats whats wrong with it. Might not be completly true... but it didnt work. i went around the block with the car and it didnt do it. it will do it some times then it will stop and start and stop.. i cleaned my maf connector. cleaned my 02 sensor and checked all my vaccum lines... anyone else have this same problem or know what it could be?

[mott6904]

What did you clean the sensor with? You can destroy a sensor really quick doing that, espically the o2. Try clean the iac valve and make sure your tps is adjust correctly.

[slowrb20]

i cleaned the maf with maf cleaner and the 02 sensoer i just used a wire bursh and cleaned off the exhaust build up...

how to i adjust the TPS?

[mott6904]

There is no point in telling... if you do a quick search in rb section you will find hella good info on how to set it... If you have a dirty idle air controll valve then your idle will surge like you explained. If you have never touched the tps im willing to bet you just need to spray some carb cleaner through it.

[slowrb20]

ill do a search on the tps... can you guys tell me where the iac is? im about 99.9% sure thats what it is and i was told i could just clean it and most of the time that will fix the problem?

[homesivan11]

its near the firewall, and has one plug connecting to it..... and it has an adjusting screw on it too......

[tlkq]

Clean the IACV. Bugger left my car not running for 5 months.

[slowrb20]

thanks guys... i cleaned the iacv and it runs alot better... it still idle surges from time to time but it auits after a few minutes... not sure what else to try but its a thousand times better now..

[mott6904]

It is probably still dirty there is a write up on austrila skyline forum(i cant remember the exact name) that shows how to take it apart and clean it everthing

[91_ka24de]

the throttle postion sensor is attached at the throttle body. its like a distributer, you crack loose the 2 bolts and adjust it from left to right which ever sounds better. Or you have blown the TPS. thats what happend with my ka24de. some times it would act fine, and have you notice a loss of power? if so i'd either check the tps. move the tps from left to right if you get no notice in the engines idel than sure enough u need a new one. hope this helps. GL

[mott6904]

dont just loosen the tps and move it around, you will screw yourself. i bet you adjust your distributor/ignition timing by sound too.If cleaning the iacv helped then thats your problem. Tps has to be set by volts and/or idle switch not by sound.

[91_ka24de]

dont just loosen the tps and move it around, you will screw yourself. i bet you adjust your distributor/ignition timing by sound too.If cleaning the iacv helped then thats your problem. Tps has to be set by volts and/or idle switch not by sound.

oh. hmm how do you set it properly then? mines in the middle of the adjustability. if my idle was bad i'd jus screw the bolt on the iacv.. can't cause any harm tho right?

[mott6904]

I dont know what wires it is on a ka but you do a continuity test on the wires for the idle switch. As soon as the circuit closed then its set, i want to say it is going to be around .4 -.5 volts(look it up on a fsm).

[PorkChopExpress]

i believe its 0.0