Replaced IAC still low idle surge pics inside.

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Kens1992mtxSHO

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I would replace the IAC. Make sure it's on the right way. Can't tell you how many times I've seen them on backwards.
 

Vnuk1

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Surge canister solenoid pictured below.VVVV
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The hose to the left I unplugged and the surging stopped. Same hose you see connected to the purge solenoid.
 
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Vnuk1

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crank cancer or vacuum leak are my guesses. (If it's not the IAC)

I doubt crank cancer but vacuum leak yes I unplugged the vacuum hose near the TB by the IAC and the idle surge stopped. But there is a round cylindrical thing connected to it the I am not sure what is is. So I assume it has something to do with that specific line or part/sensor.
 

hawkeye18

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The hose on the left is the canister purge line. It goes to the charcoal canister in the driver side wheelwell. If the engine is expecting to pull a vacuum through it, and for whatever reason it's plugged, then yes, it can cause stumbling. Alternatively, if it's not expecting flow through there and it's leaking, then you have a vac leak. I'd replace that canister purge solenoid (the brass looking thingy) as they quite often go bad. I've had two go bad on me.

I just got done with the driver's side suspension. I had to drill through the pinch bolt and the subframe bushing bolt. I ended up using a 2" hole saw to cut an access hole in the rear unibody outboard of where the subframe bushing bolt goes and using a bolt/nut setup to mount it.

My... god... I gotta tell you, that was way more effort than it was worth. Also, close to $400 in parts already, and that's not including the struts/springs themselves. The passenger side's been soaking in PB blaster for two days now, though, so that side should be a lot easier...
 

Vnuk1

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Yeah I bet you wish your problems were as simple or small as mine right about now huh? Well I guess it is off to the parts store this weekend but still broke so I don't know how I will pull this one off. Kiss up to the old lady I guess.

Yes when I disconnect that hose it runs fine, but as soon as it goes back on idle bog city! So I guess that should answer my question that it is plugged somewhere or the solenoid is not opening or bad.
 
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Storm-Chaser

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First, did you actually replace the IAC (as Ken suggested), or simply clean the old one?

Second, the fuel purge solenoid has two additional vacuum lines running from the bottom Tee - either of which could also be leaking.

Third, just because you "cleaned" the IAC, doesn't mean you corrected the problem (or worse, didn't damage it). There have been prior discussions where it was found that some cleaning compounds actually damage the plastics inside the IAC, producing either no improvement, or only short-term temporary improvement.

That's why re-Search-ing your problem is so important, because sometimes the prior corporate knowledge to issues like this, gets "lost" over time . . . .


:burnout:
 

Storm-Chaser

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Hey Jason. It may take more than just soaking.

Escorts are especially bad for the pinch bolts twisting-off during removal. This is because the rust that breaks loose from the treads as the pinch bolt is being backed-out build-up in the threads and effectively act like loctite, progressively seizing the bolt until it snaps.

As you back the pinch bolt out. Go a half-turn out, quarter-turn back (just like you do with a tap). As you begin to feel resistance, go a half-turn out, quarter-turn back, resoak with PB, and rock the pinch bolt back-and-forth until you feel it freeing-up. Repeat the soaking/rocking routine every time if you feel additional resistance as you're backing the pinch bolt out.


. . . .

[thread hijack]

I just got done with the driver's side suspension. I had to drill through the pinch bolt and the subframe bushing bolt. I ended up using a 2" hole saw to cut an access hole in the rear unibody outboard of where the subframe bushing bolt goes and using a bolt/nut setup to mount it.

My... god... I gotta tell you, that was way more effort than it was worth. Also, close to $400 in parts already, and that's not including the struts/springs themselves. The passenger side's been soaking in PB blaster for two days now, though, so that side should be a lot easier...
 

Storm-Chaser

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As a "temp" fix, go to the junkyard and grab a couple of Emissions Purge Valves (that's what they're tehcnically called) along with the best vacuum lines you find, and pay for one. They may even let you walk with the part.


Yeah I bet you wish your problems were as simple or small as mine right about now huh? Well I guess it is off to the parts store this weekend but still broke so I don't know how I will pull this one off. Kiss up to the old lady I guess.

Yes when I disconnect that hose it runs fine, but as soon as it goes back on idle bog city! So I guess that should answer my question that it is plugged somewhere or the solenoid is not opening or bad.
 

Vnuk1

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Well it was the Purge Solenoid I took off the Vacuum line today while it was running and tried sucking on it to see if it was open and sure enough it was closed. So I bypassed it and hooked up the vacuum line and it runs better than ever!

Thanks for all the help I was quite puzzled for a while there.

Oh and Storm I did research quite a bit before posting this thread to begin with so the search button is not new to me:). Most or all other threads people have replaced a hundred different parts so it is hard to determine what symptoms go with which part/problem. And It's not like I was using WD-40 to clean my parts with I have been around a repair shop for most of my life and know what types of cleaners to use. But thank you for trying to help I do appreciate it.
 
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Storm-Chaser

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I wish more people would reference/resurrect some of the older threads, for this very reason (to prevent loss of prior knowledge by appending to it).

I do recall one of the IAB threads, and there was some discussion that not all carb cleaners were the same (ie. in reference to their effect in the IAB's internal plastics).

Unless people specifically mention having searched, it's difficult to tell who has and who hasn't. I also like adding the info, so it's there for future forum reference.
 

Vnuk1

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You forget I resurrected an old thread Hawkeye18 made from like 2005 about his squeaking front end Ecco the dolphin I think. Yeah I checked tons of past theads even found one with my exact problem and unhooking the same Vacuum line but it was never resolved. Dude just said oh it is fixed now replaced a bunch of stuff now it runs fine. I was like arggggghhhh so I feel your frustration with new threads that have been covered a hundred times already.
 
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Storm-Chaser

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It's not anything to do with frustration. What I think most don't realize, is that even though the forum is decent sized and there's a good bit of searchable information, "the" person that has [their] much needed answer may not visit the forum daily or even weekly. Thus people run the risk of not having access to years of accumulated community knowledge, that would otherwise help correct their problem. Hence why I always push the search function.
 

Vnuk1

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Yes I see alot of users that I have never seen before when searching through old threads. Some have not posted for years and some only come one once every couple of months.
 

Storm-Chaser

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And often those are former SHO-owners with many years of experience with the SHO, that have moved on to other vehicles. So once their knowledge/posts are no longer referenced/referred to, that information may be forever lost . . . .

Bringing-up those "stale" threads brings it to the attention of new, currently active members, some of which will remember and be able to pass-on that information. But if the thread is never resurrected/referenced, once the forum posts are lost during a server crash, so unfortunately is that experience until someone figures it out again.
 

hawkeye18

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Not to mention that Beth prunes really old threads frequently during any given forum refresh/backup, so...
 

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