What is this? (take 2)
10-11-2003, 09:21 PM
#1
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What is this? (take 2)
Okay, I cleaned up that connector (https://rennlist.com/forums/showthre...threadid=92842), but I was still having hesitation problems under acceleration. So I found what looks like a vacuum advance thing, and disconnected it to see what would happen. Apparently, it fixed the problem! Does anyone know what the heck this thing is, and why disconnecting it would fix hesitation problems? (I drew in yellow to show how the vacuum hose used to be connected)
10-11-2003, 10:17 PM
#7
Race Car
looks like the heater valve to me
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10-11-2003, 11:13 PM
#9
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Oh yeah it's the S2 again. I bet the problem is the AFM, which probably isn't letting in enough air sometimes. Unplugging that vacuum line lets more in, which is why it's running better now. Does that seem logical?
10-11-2003, 11:37 PM
#10
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Didn't you have a bad connector or wires to the PS pump? Those are apressure switch that kicks the idle up when it senses higher psi on the PS pump. It works along with the idle stabalizer valve. It's just to help keep a smoother idle under loads. if bad wiring is the issue, it may keep the IV from working properly or at all. I'm not sure how it is wired. HTH
10-11-2003, 11:54 PM
#11
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If you have to disconnect a vacuum line to make the car run better, then something is wrong and you need to figure out what. You can bet the engineers didn't say, "hey lets design it so that you have to disconnect something so it will run better". I'd just start tracing vacuum lines (and yes, I know they go all over the place) until you find your problem.
10-12-2003, 03:38 AM
#12
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Thats the heater control valve, its connected to the top of the waterpump then runs parrellal down the steel pipe parrellal to the head. Vac operated, might want to open and close your heater control valve and see if vacuum is present when the hot/cold switch is operated. You might be introducing a vac leak when upplugging it making the idle a little smoother/faster? How does the engine run when you put your finger over the opening?
10-13-2003, 01:26 AM
#13
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For the record, it was indeeed the air flow meter. I took it apart yesterday and made the arms follow new tracks as described at http://frwilk.com/944dme/afm.htm . I think by disconnecting the heater control valve, I was letting in more air to make up for the air flow meter's incorrect values. When I first put the AFM back in after adjusting it, the car ran like total crap. But then I remembered that you have to disconnect the battery to clear some memory. After doing that, it now runs better than ever before!