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ilde stabilizer valve

Discussion in 'DIY (Do-It-Yourself)' started by mac townsend, Mar 19, 2009.

    mac townsend guest

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    2.7 eta engine

    the idle stabilizer valve ("ISV") is the thing that's about 6" long and an inch or so in diameter, connected to the cold start valve with a 3/4" (or so) hose and to the air intake just prior to the intake manifold by another 3/4 hose.

    There's also a two-prong (in my case) electrical connection at one end. At the other end is one hose, and an inch or so back from that end is a right angle connection for the other 3/4" hose.

    Bentley manual shows the short 3/4" hose connecting the ISV to the Cold Start Valve to come off the right angle connection and the hose from the intake inlet to connect to the ISV at the end of the piece opposite the electrical connection. So the ISV is perpendicular to the axis of the engine.

    My car had it plumbed in backward..from that, intake plumbed to the right angle and fitting on the end plumbed to the Cold Start Valve.

    I've been having problems with idle, either too low or too high...although running a 195° F t'stat (in place of an189° same) has helped by bringing temp (gage reading) up to just shy of 1/2 from just shy of 1/4.

    Just noticed the variance, so swapped the ISV to match the pic (#6-10) in the book. Seems to have made it worse...not is idles at about 1000 and revs to 1500 then drops back down. It may take a bit of time for the computer to "get used to" the different fitment (? I see that changes like this often take 5-10-15 min of running before things return to where they ought to be)

    I'm going to test the valve (per Bentley) in the morning when it's about as cool as it will get.


    But...is there a functional difference in the way the thing ought to work....At first thought it seems that when the valve opens air flows regardless of which is the supply line??
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    mooseheadm5

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    Please take a picture, as I cannot follow your description. Anyhow, the idle control valves on these cars are known to be problematic at this age. Normally, you need to replace both the ICV and the control unit (the green box above the ECU in the glove box.) You can adjust your ICV a little- there is a screw that is either accessable from the outside or from one of the ports.
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    az3579

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    +1 to what Paul said. I had an issue where the idle was at a constant 3300RPM, which is completely unacceptable and made the car nearly undriveable. I replaced the idle control valve (ICV) and it still did it. I then replaced the ICM (Idle Control Module) and all was almost fine. Here I am with the "new" ICM and valve, and the idle still isn't entirely what it should be. Now, in the mornings or whenever the engine is cold and is first started, it revs up normally and idles fine, but when you give it some throttle and let go, it bounces around uncontrollably and occasionally bounces so low that it stalls.


    I don't think you'll have an easy time finding used hardware that works just right, other than new parts, but where are you going to get those other than a stealer?

    mac townsend guest

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    no photo, but I can make an ascii drawing:

    |--------------------------|-|----|__
    |---------------------------------|


    OK. at left is where the wire connects. at right ( the __) is one hose port. At top ( | |) is another hose port, one that is at right angles (90°) to the axis of the valve body.

    Now..the hose connected to the right angle port (| |) goes where? To the other side of the engine (across the intake manifold) or to the cold start valve right next to it?

    I had it hooked up with this hose connected to the other side of the engine (just as the rubber connector from the air flow meter enters the cast manifold). This is the way the car came to me. I've used carb cleaner then WD40 to clean in the valve movement and it seems to move freely. I can feel it pulsing with the power on.

    Idle was not really bad, sometimes it was perfect, sometimes it dropped too low (dropping too low just happened recently--idle was pretty much stable after I put a warmer t'stat in place).

    A picture in Bentley suggested I had it hooked up wrong, so, ever the explorer, i switched it so that port is connected directly to the cold start valve (a couple inches away). Now it idles very high and constantly guns itself from 1,000-1,200 to 1,500 +

    Once off idle it seems to run ok.

    Was unable to start checking individual pieces today because one of the Allen screws is rounded off. Got an extractor today and if it is not pouring rain tomorrow (supposed to rain hard tonight) I'll start checking.

    I sus[ect I'll find nothing amiss and that I'll end yp replumbing the thing back to the was it was origina;;y...but there is still the illustration in Bentley...
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    mooseheadm5

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    I'd just put it back the way it was before. I don't have any old small 6 cars to look at, so I couldn't tell you which is correct, but if it worked better before, I'd go with that.
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    az3579

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    Here is a picture of the entire setup on how it "should" be done:

    [IMG]


    And here is a closeup of the ICV:

    [IMG]



    Hope this helps...

    mac townsend guest

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    TNX

    If I hook it up that way it runs like caca

    if i swap the hoses it is a little better.

    Now I know how it should be, and that give me good information. Thanks!

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