Pelican Parts Forums - CIS Mixture screw question

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CIS Mixture screw question

Is there any sort of visual indicator that the screw is actually turning, my car currently wont start and I cant figure out if I need to turn left or right as I cant get it started? I know the screw pushes the sensor plate arm up or down is that piece of the screw visible from within the air box that may help me find center again? I dont feel anything moving when i'm turning it, also should it push the plunger down when you get it in the right spot?

There should be no need to adjust the CIS mixture screw just to get the car to run. Even a badly-adjusted idle mixture will still start with your foot in the throttle a bit.

Was it running previously and now won't?

Do you have spark? Compression?

What year car/motor?

Yes it was running up until I touched the mixture screw. I have spark and compression if I give it gas occasionally it will start but then dies when I remove my foot from the gas wont hold the idle.

Quote:

Originally Posted by fanaudical (Post 12063417)

Quote:

Originally Posted by harv666 (Post 12063441)

Yes it was running up until I touched the mixture screw. I have spark and compression if I give it gas occasionally it will start but then dies when I remove my foot from the gas wont hold the idle.

Probably a new basic setup is required supposing no vacuum leaks proved and every part of the CIS system is working properly. Again: Every part of the CIS must work in spec and no vacuum leaks!!
Vacuum leaks are the biggest enemy for CIS systems!!

I had exactly the same issue (engine won't hold idle speed when cold and a hard start and no start possible on ambient temps lower than 10°C/50°F) I purchased the car with lots of issues...
Conclusion: The mixture was way too rich due to several issues. I was able to keep it alive with the throttle as well...
With pushing the throttle you give the engine more fuel but also more air to burn it. I bet it smells heavy of fuel by holding it on idle with the throttle?

I your case I firstly would do a basic setup of the CIS. The procedure is described in detail by Curt form klassikats.com on his YT Channel in this video:
https://www.youtube.com/watch?v=K-OvjlkrgNo

But the whole video series about CIS is definitely worth a look before working on the CIS:
https://www.youtube.com/playlist?list=PLkWFofpgz2OgF9FdliKnlzuY0pygqRkMj

Good luck!

Thomas