**Weird Idle on cold starts**

[kvahag]

Hey everyone, my friend is having a problem with his s13 and I hope someone can help us out.

The problem is that when the motor has completely cooled off and when he starts it the rpms suddenly drop to almost 0. The car almost stalls but then it goes back up to 1000 rpm, and then back to 0, and then back to a 1000, and then back to 0, and then to normal idle. What could this result from?

Thanks in advance guys!

[makulit054]

need more info on the setup?

[kvahag]

stock ka24de

its just been acting weird every single time he starts it up cold

[warpd]

Idle air control valve? Only thing I can think of off the top of my head.

[kvahag]

yea my friend thinks its the idle air control valve too, i just wanted to get other peoples opinions before he drops money on a iac valve

[SoguRacing]

IAC or maybe a faulty coolant temp sensor.

[awesomenick]

Before buying a new one, he should try to clean it out/ test it. There's tons of info about this online, so you shouldn't have trouble finding it.

[kvahag]

found out some more info that might help figure out the problem!

he told me when he turned on the car the other night, it had the same almost stalling problem...and each time the rpms would drop so would the electricity level. like the interior lights would dim and light back up then dim again.

and he just changed the battery, can this be the alternator?

[makulit054]

I don't think it's the alternator. the drop in electricty is related to your rpms dropping. It sounds like temperature related. IACV and engine coolant temp sensor, have you checked those yet. check the voltages.

[kvahag]

I don't think it's the alternator. the drop in electricty is related to your rpms dropping. It sounds like temperature related. IACV and engine coolant temp sensor, have you checked those yet. check the voltages.

going to clean the iac valve this weekend.

[suislide91]

same thing happend to me, mine would go from 1500 rpm at start to then drop to 200 rpm, barely hold on then die. several times and die. i replaced the alternator, new ground wires and re-did my timing, worked for me. try it?

[kvahag]

same thing happend to me, mine would go from 1500 rpm at start to then drop to 200 rpm, barely hold on then die. several times and die. i replaced the alternator, new ground wires and re-did my timing, worked for me. try it?


never dies...its just drops and goes back up and repeats. iacv cleaning tomorrow, we'll see how it goes.

[suislide91]

hmmm i see i see. good luck bro