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high idle

Recently the weather here's been in the 10-15degree range. I'm not too sure what's going on, but for some reason, 23's been idling around 1800-2500rpm which bugs the crap out of me since it's already hard enough that the gears won't engage smoothly. Also, the stock temp guage has been on and off on operation. What i noticed is that the idle is high when the temp guage is reading at zero, and the idle gets lower when the temp is nearing normal range. But with all this, it still won't idle
 

do you have a logger? If you dont get one asap and put mmcd on it. Did it just start doing this or has it allways been like that? Could be a bad temp sensor or idle air control motor on the tb could be stuck open.
 
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No logger here. will be stopping by ams tomorrow to see what's up with it. I'll try to see the idle air motor tonite.
 

turbowop

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Could be the thermostat stuck open not allowing the coolant to warm up enough to melt the wax pellet in the FIAV on the throttle body, keeping it in constant warm-up mode. Possibly the FIAV itself could be having issues. Could also be an issue with the ISC motor, but I doubt it.

You used the correct procedure to set the BISS didn't you? The one that takes away the ECU's control of idle and centers the ISC? Does the car still have coolant lines running to the throttle body?
 

i think john did the deletion of the coolant lines. I haven't done much to 23 yet. I'm thinking the thermostat's stuck open as well. I noticed the plug for the sensor was lose a few days ago. I cleaned the connection and plugged it back in, and it idled a bit better, but after a 5-mile trip, the idle was back up again.
 

turbowop

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Sweet, that's your ISC motor. /ubbthreads/images/graemlins/hsugh.gif

You can't tell if the FIAV is blocked off from a picture. Obviously, the bottom half of the TB is still there though, and that's the part that houses the FIAV. If it hasn't been blocked inside with JBweld or with a plate in between the throttle body halves, then I think we found part of your issue.
 

If it wasn't blocked of in any way, would i be able to feel any pressure (in or out) through those openings? I wasn't feeling any at all with the engine running
 

turbowop

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No, those nipples are for coolant only.

I don't see a blockoff plate sandwiched in between the two halves. If you could find out from the guy that deleted the coolant hoses whether or not he blocked the FIAV off with JBweld, would help a ton and you wouldn't have to remove the TB to find out. If he didn't block it off you should pick up the factory TB coolant hoses and hook them back up. Get some coolant flowing in there and if the FIAV is working properly you should be in better shape than you are now.
 
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i'll check with john on the blocks he used if any. As for their lines that were previously there, where do those route to/from?
 

thecman02

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With your temp guage jumping around... I think you need to look at the wiring on your temp sensor maybe. If the engine thinks it is cold.... it will be on a fuel map with much more fuel.... which would raise idle. Otherwise definitely listen to the above.
 

the temp sensor connector seems a bit sketchy, i'll take a closer look tomorrow/tonite if possible
 

The engine has 2 temperature sensors. The one that controls the gauge doesn't affect the ECU. It has its own sensor.
My vote is that the FAIV was not blocked off with JB Weld. /ubbthreads/images/graemlins/banghead.gif
 

any other sensors also anywhere i replaced with new female ends with shrink wrap and did them up nice nice. Even if i had the slightest doubt i redid them. Worth the cheap money to do it and pays off in the long run, its pretty crazy how much these cars rely on the coolent temp for running maps etc is insane. One weak connection and it throws everything off. Good luck, keep us updated.
 

turbowop

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Quoting wasabiz45:
As for their lines that were previously there, where do those route to/from?



You want the ones I circled below in red. #32 connects to the thermostat housing and #33 to a nipple on the water pipe. The pic shows how both of them route.


 

for the small amount of time, you guys have been a big help. i'll look into this when i get back home. currently getting all this info in my CAD class, hehe. THanks for the look out fellas.
 

turbowop

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No problem. Idle surge and other idle issues are a huge pet-peev of mine, so I got pretty good at diagnosing them.

For what it's worth, on 1051 I JBweld blocked the FIAV since it wasn't working correctly but I still run the FIAV on 503 since it works great, especially on cold mornings. I also just diagnosed an idle surge issue with 503 that turned out to be a bad ISC motor. Both my cars idle like champs. /ubbthreads/images/graemlins/grin.gif
 

strokin4dr

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Savannah, GA
Quoting turbowop:
Idle surge and other idle issues are a huge pet-peev of mine,



+ 1000!!!
Is seems like every racer-boy DSMer that I meet around here has a car that is searching for idle, and they seem to think nothing is wrong. /ubbthreads/images/graemlins/rofl.gif
 

insane92

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1342 just started doing the same exact thing yesterday. I haven't had time to investigate it yet, but I'll look at it tomorrow. Also, my 1g had similar problems last summer and also had idle surge, and it was the ISC and the FIAV. I replaced the ISC and blocked off the FIAV and it's been fine ever since.
 
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