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SLO-S13
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Discussion Starter · #1 ·
Alright so it's time I take care of the far too high idle in my car I think. Around the end of summer I was having issues with my car but couldn't deal with it due to two broken arms! Brought the car to the dealership, they called me said some stupid shit and I picked my car up with it running worse than it was before bringing it there.

Brought the car to another shop and was told I had some wires in the wrong order on the distributor (thank you Nissan dealership), and a couple vacum leaks but that I had burnt valves. Compression was fine on the car however but it was still running like total shit for me so I decided to replace the ECU and vuala fixed the issue.

Now to get to the problem!
However my car has since then been idling at about 1000-1500 and I just don't understand why. Possibly a vacum leak? The idle screw is gone (Thanks Nissan again?) but even so that shouldn't make it idle high it'd make it idle lower. So what do you guys think? I'm thinking of just pulling the intake manifold and replacing the gasket for it and the runners as well as replacing all the vacum lines in the area. Is there anything that could possibly be shot (IACV?) thats making it idle so high/fluctuate so much ? I set the idle speed on the ECU to what it was on the old ECU so I know that couldn't be off. Thanks in advance.
 

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unplug your TPS and see if it still goes up and down. also an high idol can some times make your idol go up and down. so to me the idol going up and down and the high idol are the same problem.
 

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SLO-S13
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Discussion Starter · #3 ·
True, I'll try unplugging the TPS although I think it's fine as it's reading normally with the AFC II.
 

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My local Nissan dealership sucks balls as well, I had a wiring issue and I don't know crap about wiring so I took it in. My car is stripped and they looked at it for a little and said they don't even want to touch it cuz it's old and gutted and they wouldn't know where to start. I got so pissed cuz they had already been getting on my nerves by taking forever to get parts to me and I just went off. "It's easier to get to the damn wires with the car stripped!", and then I said something like "if your mom was stripped I'd know where to start" and drove away. :rotflmao my buddy that was with me was shocked cuz I'm normally the quiet, polite guy who just takes in the butt from these dealer folk.
 

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:werd i was having and still do the same problem. I replaced the wiring harness because it was all cut up from the previous owner as well as the ecu. Idles a lot better but still fluctuates periodically. Also, the car bucks/ stutters as well and my MPG sucks balls. It runs rich for a fact but everyone i brought it to cant figure it out, even the dealer. Also the egr is blocked from the previous owner as well but wouldnt that make it run leaner??

Thanks, George
 

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alot of dealerships cant find problems because they see thats its just not worth there time. dealerships suck you need to take it to a good private shop. or do it your self
 

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i say its a Vac leak or my problem was the IAC valve was stuck open. which if you dont want to buy a new one and install it cause its a pain in the ass, you can simply restrict the hose that comes off the intake pipe and goes to the IAC with a small funnle or a tip of a bottle like from a Lucas oil bottle. this restricts the air flow so the car will idel lower. you might have to play with it a lil to figure out how big of a hole you need to use. mine is right about 1/4 inch. and now i idle right at 900 a lil high but not enough to cause prolems. and its a steady idle
 

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incorrect timing will cause high idle... check your timing...

There are very few places on the KA where you can have a vac leak unless you have a late 96 or up...

There is an idle speed screw at the back of the manifold on one of the idle control solenoids... screw it in to lower the idle... out to raise the idle..

Check that your throttle body is closing all the way..
 

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SLO-S13
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Discussion Starter · #11 ·
TB is definitley closing all the way, I'll check the other stuff though. Thanks for the tips.
 

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I have a similar problem with my GST (I can't wait to sell this POS) and it turns out it's a worn valve guide. I fixed every single part that could cause a high idle before I got that far. Have you done a compression test?
 

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SLO-S13
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Discussion Starter · #13 ·
colonelfox said:
I have a similar problem with my GST (I can't wait to sell this POS) and it turns out it's a worn valve guide. I fixed every single part that could cause a high idle before I got that far. Have you done a compression test?
Yeah, compression is perfect on it which is definitley a relief hah.
 
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