dkim1985

Hey guys.
I just installed a new TPS at 0.46-0.47v and now my idle has jumped up to around 1200rpm. before it was at 700rpm at 0.50v. i have the idle control screw turned all the way. no vacuum leaks.

how do i fix this to bring it back down to 700 or atleast close to it??

it's a s13 ka24de. only mods is exhaust, new air filter..and a few other things that don't have to do with the idle(radiator, power steering, etc)

UPDATE;
When Im driving and drop the clutch, it'll idle around 700rpm. But when the car comes to a stop or slow roll, then it'll go back up to around 1200rpm.
anybody??

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dkim1985

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cotbu

They are wot\full throttle voltages!
readjust the tps to .45v closed throttle!
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dkim1985

oh sh*t! i just realized it was a typo. LOL
i meant it's currently at 0.46-0.47v

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inopsey

you must close how much your tb is open at idle by adjusting the screw that it sits on when closed. then adjust the tps again

dkim1985

are you talking about the throttle cable? because at idle, it's closed all the way i believe..

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steve shadows

Yes it should be the little tiny 8 mm screw and nut that props the actual throttle plate open slightly on the throttle body itself. Otherwise you can try adjusting the actual tps slightly down and see if that readjusts the idle. The TPS is a range sensor so you can adjust it slightly off the suggested voltage range for calibration.

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dkim1985

Ohh interesting. I'll do this tonight and see if it helps.
I don't know if this makes a difference or not but..
when the car is at stand still, it'll idle around 1200. if the car is moving and i drop the clutch to put it in neutral it will idle around 700 until it comes to a stop or slow roll..jump back up to 1200.

question if the throttle is closed all the way(at idle), would that cause the rpm to jump up during idle?

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steve shadows

Failing IACV maybe or a vacuum leak somewhere...possibly

Also high timing. Your base timing could be all jacked up- need to check this.

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dkim1985

It's probably the throttle body because my engine was running fine and i had JUST gotten a smog check. (passed)
I had to change out the throttle body because of something else..
I have a new TPS that was used during the smog check, using that same one now. just the throttle body was replaced with another used one.

Just wondering if opening the throttle plate during idle will be the proper 'fix' for it. I don't think my original throttle body had the plate open during idle..(ran fine)

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dkim1985

Ok. So i just did this, this morning, before heading to work..
At idle, I was able to lower it to about 800rpm..
But when i started driving..if I drop the clutch, it'll make the rpm dip really low and I even stalled once. Had to keep the AC going so it doesn't stall.

So I'm going to raise that bolt/screw back up to where it was before because it doesn't seem like that was the problem. I also readjusted the TPS(0.45v), doesn't seem like that was a problem either.
I don't think I have a vacuum leak because the 'moving idle' and 'stand-still idle' AND when driving..the rpm is pretty consistent and doesn't waver. (I've had a vacuum leak before so I know what it feels like).
It's only when I'm at a complete stop or slow roll the idle will go up. I've tried adjusting the throttle cable, doesn't make a difference.
Is there a way I can test/recalibrate the Idle Air Control Valve?

Edit;
I read to test the Air Regulator, you have to pinch a hose? What hose do I pinch? And what is that supposed to determine?

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dkim1985

raised the throttle bolt/screw.
idle is back to 1200 at stop..700-800 during neutral cruise.

TPS is currently at 0.40v.

any ideas?

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jr_ss

Put your throttle screw back to where you had 800rpms at idle and adjust your IACV slightly up to 850-900rpms at idle and see if it stalls then. If so, adjust the IACV again to idle slightly higher. You should be able to find a sweet spot. FYI, my SR idled at 1k all the time or slightly under, it's where the car seemed to run best. Anything lower and it wanted to stall at times.

Do you have a vent to atmosphere BOV on the car by any chance?

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locoluna825

Is your car converted from Automatic to manual??

inopsey

did you set the aicv with the tps unplugged and the car fully warmed up? i think you need to re adjust the tb screw again and set the aicv properly.

dkim1985

i have unplugged the tps and let it run for a bit and the idle screw is turned all the way to the right and it still idles about 1200. when i plug the tps back in, it might lower a bit but it'll eventually go up back to 1200.
BUT..when im driving and i drop the clutch and just cruise..it'll idle about 700-800 until i come to a slow roll or stop where it'll go back up to 1200..

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dkim1985

So I tried to do this again.
Unplugged the TPS after driving on the freeway for about an hour(on my way home from work).
Let it sit in my drive way idling for a bit, the rpm stayed at about 1200.
Tried to adjust the idle screw..it was turned all the way to the right so it wouldnt be able to lower the idle at all..
Turned the car off, plugged the TPS back in, the idle dropped a little about 900 for a few seconds but still went back up to 1200.

so...nothings changed.
Please keep in mind, this is only when the car is at a stand still or slow roll!
If I'm cruising +20mph..with the clutch in, the car will idle at 700-800.
As soon as I stop, the idle will go back up.
I'm going to try a few things this weekend;
-spray some carb cleaner into the IACV while engine running to clean.
-check if theres any air leaks

Anything else I should check while I have time?

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dkim1985

I noticed while idling at stand still..it smells rich..still idles at about 1200.
Did a quick smoke test to see if theres any leaks...nope. only saw the smoke coming out of the EGR valves which I think is normal(?) correct me if I'm wrong.

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Frank_Jaeger

Replace the IACV. You have no choice.

Hoffman5982

Instead of starting a new thread, I'll ask here. I have an s14 SR and out of nowhere it started idling high as well. Like 1500rpm. I've adjusted the IACV and checked the TPS but can't fix it. What I did notice, however, is that if it starts to idle high I can shut the car off and start it again and it's perfect at 800rpm. Any suggestions? I'm about to pull the IACV off and clean it.

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dkim1985

yours sounds like the IACV. mine was the throttle body. maybe the plate was bent or something. i put in a different one and it idled fine.

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