David, we too have this problem. I think that the idle stabilizer is sticking on the central shaft. The shaft is probably worn from constant movement around the idle position. When the engine needs to rev higher - when cold or when the A/C is on - then the stabilizer is holding the valve open wider, outside of the worn zone, and isn't sticking. To test your IS valve, try spraying a small amount of fine oil into the air intake of the IS valve (engine off) and see if the symptoms change. Larry > <snip>Then, I exchanged the idle stabilizer valve itself. > Now, it idles when cold, but after driving even a little, I notice the > idle speed going up and down in a regular fashion every couple of > seconds. It doesn't go up a lot, but it's noticeable and new. This is > all with the AC off. When the AC is turned on, the idle speed comes up a > bit, and there seems to be less fluctuation though I still notice a > tiny bit of the up and down.<snip> |
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