Pelican Parts Forums - '83 CIS cold start low idle issue

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Maybe this problem is more common than expected. My AAR works as intended, apparently. Open when cold. Closes fully after a minute or two. Won´t idle when cold, without feathering the throttle. With throttle I can keep it steady around 1100 rpm. Idles by itself around 950 after a minute, but hunting slightly, while warming up. Steady idle 950 when warm. I suppose its running slightly rich until warm. Runs great when warm. Tony´s smoke test next. Has anyone removed the CSV flange without dropping the engine? Or am I best of waiting until I at one point do drop it? I haven’t, at the time, got any other reason to drop it, and I can live with the car running as is for a while.

i removed and drilled the csv flange without drop. It is NOT fun :)

Quote:

Originally Posted by wreckah (Post 10393055)

i removed and drilled the csv flange without drop. It is NOT fun :)

Sweet. It´l depend on my mood towards spring then :D

I did a partial drop (lowered the rear of the engine a few inches) and got the CSV flange loose but the hose attached to it was so stiff, I couldn't get it loose. After all that work, I ended up dropping the motor anyway. So much easier, especially the CSV install with motor removed. Incidentally, when I got everything back together, the decel valve was not working properly producing a continuous high idle. Unplugging the vacuum hose (and plugging it) brought everything back to a nice idle. My take is you don't need the decel valve anyway.

Incidentally, I have found 3 CSV flanges in my spare parts jungle and they were all the closed variety even though the systems they came from were later US or Euro CIS. Makes you wonder...

Decel valve delete.........

Quote:

Originally Posted by JB (Post 10393121)

JB,

You could remove the decel valve if is defective or leaking. But you need a good working DV. People who removed it does not understand how a good working DV plays an important role in the operation of CIS. If you strongly believe that there is no need for a DV in your engine and would make you happy, nobody could stop you from doing so. It is your car and not ours. And I won’t do it for my engines. The lack of understanding and knowledge is difficult to overcome. Keep us posted.

Tony

Tony,

Lack of understanding and knowledge is not difficult to overcome if someone such as yourself is willing to explain it to someone interested in learning.
Please enlighten me as I am always interested in learning.

Jim