high idle

[Kure91]

Car 1990 240sx (ka24e)

I turn the car on ildes real high (4-5k) I give it gas it goes up but when i let off idle doesnt go down. I unplugged the tps and car starts after a few tries and idles at 2k but cuts off after about 30sec.

I have cleaned iacv and intakeNew fuel filterNew engine temp sensorChanged maf with a known working one

Any other suggestions????

i also have been searching for instructions on how to adjust the tps, anyone know how to do that????

[Razi]

Have you tried adjusting the iacv? Does it do anything?

Sorry I'm not much help, I have no experience with the SOHC.

http://www.nicoclub.com/FSM/240sx/1989-90/That's the link to all the Factory Service Manual pages for the KA24E.Perhaps you should download them all and look through them.

[Kure91]

ok i downloaded the fsm and the ecu gave me a code 55 but i only see a 45 (red blinks 5 times and green blinks 5 times)....anyone know what a code 55 is????

EDIT....nevermind code 55 means all clear

[Razi]

Hm..Have you checked your throttle body adjustment recently?Maybe it is slightly open and causing a high idle.

[Kure91]

on the throttle body???? If your refering to the throttle cable adjustment yea, but i need to get the right size wrench. I turned the iacv all the clockwise and it still idles high but when i give it gas the rpms drop (like its trying to go to the correct rpm). And all i keep finding is tutorials on the dohc.

[Razi]

Odd..I've never had my car idle that high before, and I have a DOHC, so I have no experience to advise you with.All I can do is guess maybe you got a leak in your intake, but that's just random guessing.

Hopefully someone more knowledgeable can chime in.

[Kure91]

thanks for your help....heres a link to a video

http://www.youtube.com/watch?v=rACuicemsyc

A couple of people have been telling me its the fuel pressure regulator, isnt that on the side of the intake on the ka24e.

[liquid_cool]

well..there are a few things that would make you run that high....vacume leak is one..bad idle controll valve..and last but not least..the hidden one..(this happend to me) under the throttle body rite where your throttle pully is..there is a set screw and nut...if the nut becomes loose for any reason then the set screw would be free to vibrate upwards "ive only know of them vibrating up..not down " this would act like a idle controll valve by letting more air in and holding open the throttle position sensor...had that happen to me and it allmost made me eat it mid drift...check it out and post back with what ya find.

[Kure91]

ok i have a question that i keep getting different answers on, is the idle control valve suppose to buzz with the key on engine off????

[blueballa]

brother!. i have the same problem as you but mine is worse. i keep hearing a buzzing noise from the back on my engine. i didnt even think about my iacv. but when i start my car. i hit 5300 rpm. so if you have a solution let me know man.