Thanks again to Beep Beep and a question; 930 decel

[scphelps1]

I just want to thank beep beep again for his very informative post on the BOV gaskets and recommendation to replace. I replaced (or installed!) 1 , but the other one was fine. I also adjusted my throttle, as I was getting maybe 1/3 of it! There is definitely more power now! After replacing the gaskets and going for a ride, my idle was noticably higher. I turned it down twice and it seems to have stabilized now. However, sometimes when downshifting or approaching a stop, now the idle hangs between 2-3000 RPM. Is this due to the decel valve? If so, why would this missing BOV gasket cause this, or is this a throttle adjustment issue? If I hit the throttle, in neutral, or with clutch in, I can get the idle to come down, although pretty slowly. I know there have been posts about removing the decel valve. I have contemplated this, but am not sure of the best way to do this. Perhaps someone could elaborate.
Thanks!

[dean]

Your hanging idle could be cause by a bad decel valve, or something else. You have to eliminate the valve to see if it is bad.

[beepbeep]

I'm glad to see that my expirience helped someone else. Leaky BOV-gaskets usually contribute to sluggish boost buildup and bad idle.

Speaking about your issue with hanging throttle, it can be also caused by throttle cable itself, friction on a butterfly-valve or faulty deccel-valve. Altough it's possible that bad decell-valve is causing your problems i would look to other possibilities first, as it seems like you started expiriencing these problems after throttle-adjustment.

You can easily check this by taking of the thin hose off the front side of decell-valve and plugging it, thus rendering it inoperable.

Also, check all small hoses for eventually leak. There is a slight possibility that high idle is caused by BOV-piston getting stuck or not moving far enough. There is quite complicated vacuum-system for pulling BOV-piston composed of thin hoses. Any leak there could prevent piston from moving correctly.

With other words: there are three "sticking" things:

1. Throttle
2. Decell-valve
3. BOV-piston

Troubleshoot them one by one and see which one is making problems.

If idle is falling down slowly then i tend to believe it's deccel-valve.

Good luck!

[scphelps1]

Thanks for the replies. I will try the blocking the decel valve hose first.