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RamThis
07-15-2006, 09:45 PM
Ok, I have my choke just wired fully open because it was not opening up all the way, and here in Tx, I dont need a choke. A few good pumps of the gas to prime it with the accelerator pump starts it every time, and fast.

But, when the engine is cold, it idles fine, sets at about 800 in gear, 1000 out of gear (still havent fixed my solenoid so have to idle it up a bit out of gear for now)

But, when the car warms up, it idles up to 1500, sometimes up to nearly 2000 rpm.

How can I disable ANYTHING that jacks with the idle speed so I can just set the stop screw where I want it and have it idle there consistently???? I dont want the idle controller hooked up, all I want is the butterfly arm to hit the stop screw, and to get my AC and In Gear solenoids working for the boost diaphragm, and leave it at that. No choke, no high idle crap.

What's the best way to get that done?

A20A1
07-15-2006, 10:16 PM
High idle is because you set you screws too high, you set them to run cold instead of where you should asjust them when the car is fully warm.

So really you have a cold idle problem.

The idle controller is good for when you turn on accessories, is only engages, or should only engage when you are under load. Load meaning your lights are on, etc. But not your A/C, the A/C Idle one is for that. The Idle Booster is for Automatic cars only. Manual cars only have the idle controler and maybe the A/C diaphragm if the car has A/C.

Anyways as long as you don't have some vacuum leak from a thermovalve or something like that then it should be fine to use the throttle controller, it even should help out with cold idle a little since vacuum will be low enough to engage the idle controller and bring the idle a tad higher.

The throttle stop screw is the lowest possible idle and that means when the car is fully warm. the throttle controller does the rest and is turned up and beyond the throttle stop screw if that is what is required.

remember all the throttle controller needs is a direct tap to intake manifold vacuum.

RamThis
07-15-2006, 10:51 PM
This car has both a idle controller (passenger side front of carb) and the double boost diaphragm for A/C and In gear (driver side rear of carb) I see what the idle controller does but their is not any noticable RPM difference between lights on or off or electrical loads. Only RPM load difference is A/C compressor on and in or out of gear. That's why I just want to make it a simple throttle stop adjustment where it idles the same hot or cold, just have it set on the throttle stop with nothing else hooked up that can effect idle, EXCEPT the double boost diaphragm, just the one that cracks open the butterfly enough to maintain the idle speed when the A/C kicks on, and the second diapragm that cracks open the butterfly a bit more to maintain the idle RPM when shifted into gear.

I really just want to make the idle just like your lawnmower, one set screw for the idle stop, and that's it. Then I will put in the new Idle Boost Solenoid in the black box that I have, and fix the Idle Boost Diaphragm so that both diaphragms work, and leave it at that.

So, what do I need to remove or disconnect to make it a simple stop screw idle setting, with nothing else effecting the idle?

A20A1
07-16-2006, 02:06 AM
Yes you can always make it run that way, thats how my keihin was. one screw.

No other diaphragms will interfere with idle if you turn out all the other screws.

There is nothing inside the carb, all linkaged and throttle adjustments are external.

Thing is you have to set the throttle stop for hot idle, at exactly the RPM you desire... then leave it alone. If you try to set it for cold idle, as the engine warms up the idle speed will increase, even if the throttle stop is the only screw setting idle.

With the weber no choke it runs fine even at 500-800 rpm in gear or out, when cold it idles closer to 500 but thats expected because idle is always lower when cold, the engine vaccum, fuel mixture, ignition, all that is having trouble when cold.

Your engine only has one idle speed and that is hot idle, the only thing that will effect it if the thorttle stop screw is your only screw will be:

Load; A/C, Transmission, other pullies.

Electrical load; headlights, interior/exterior fans.

Temperature; combustion temp, spark plug temp (ability to clean itself of carbon deposists in order to fire properly the next time ), Fuel temp ( if not in vapor form it doesn't burn well or never reaches the combustion chamber and puddles in the manifold ). Air temp ( can be too cold and cause fuel vapor to condense ). Oil temp ( oil too thick at cold temp adding excess friction making harder to turn oiled parts ).

So you can set your cold idle speed to 1000 rpm to make up for all those problems, but as soon as they go away you idle speed will raise to 1200 or so.