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On 27 Feb 2006 at 23:59, Constantino Tobio wrote: > So I have the AAR more or less sorted out- it closes nearly completely > when 12V is applied to it, and opens as it cools down. Tough thing is > that it doesn't close 100%- there's always some suction, even on a warm > engine (that is, idling for 20 minutes, I can't drive it since it's not > registered yet). However, when I put my thumb over the hose, RPMs drop > to 5-600. So fully sealed is probably not a correct state of affairs. This kind of valve never seals perfectly, but it DOES cut down the airflow to next to nothing. Feeling for suction is the wrong test. The right test is to see if the idle changes noticably, once warmed up, when you close off the opening with your thumb. > My idle now stays around a range of 1100-1200 and fluctuates, and when I > accelerate RPM dips a little and then throttles upwards. Both these > things don't seem normal to me. The former, should I adjust the idle air > bypass to get it down to 950 RPM (it's an Auto) since it seems like I've > reached the right point with my AAR? The fluctuation seems strange to > me- is that much fluctuation normal? I would almost think that there's a > vacuum leak. As for the dipping during acceleration, it almost seems > like the throttle valve isn't doing its job of sending the extra > impulses immediately to the injectors, but I can very clearly hear the > injectors fire when the car is stopped and I move the throttle. A wild hunting idle is normal if the idle is set too high. Put it down to 900- 950. Make sure you have hoses on all the nipples, or you won't be able to get the idle down properly. It's also possible that there's a vacuum leak somewhere, but I recommend that you NOT do the typical fix of adding hose clamps to all the fittings. The 4 short large hoses at the sides of the IAD are often suspected of leaking and I see a lot of hose clamps on those when they're not needed. Instead, take care not to tighten down the IAD before the intake runners are tightened. Then you may want to rotate the large hoses so that they are in their most unstressed orientation. In the worst case, you may find that the leaks persist for a few thermal cycles and then go away on their own as the hoses reconform to the shape of newly installed parts. > I'm trying to sort out the idle so I can adjust the timing properly. I > checked the dwell after I adjusted it by feeler gauge- I'm at a dwell > angle of 44 deg, which is a pretty good start- I'm going to try to get > it to the recommended 50 deg. 44 should work fine, but 50 is better at high rpm. -- Jim Adney jadney@vwtype3.org Madison, WI 53711-3054 USA ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ List info at http://www.vwtype3.org/list | mailto:gregm@vwtype3.org ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~