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Warm up regulator and A/c control panel ?'s

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Old 11-30-2007 | 03:24 PM
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Default Warm up regulator and A/c control panel ?'s

I have an 80 manual and was wondering what the warm up regulator does and where it is located. Also on the interior A/C control panel, I removed mine and there are some wires on the back of it that are broken but they look like clear strands inside of a black sheeth, what are they? They seem to stick into various openings but dont really connect to anything inside...
Old 11-30-2007 | 05:20 PM
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On the AC Panel - you mean the head unit with fan speed & sliders/

If so they are fiber optic tubes - light guides from the one HVAC head unit bulb to the sliders. These should be illuminated at night as should the logo/colored panels around the sliders and the fans speed indicator digit.

Alan
Old 11-30-2007 | 05:24 PM
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I am sure Jim Bailey will give you a much better breakdown of the purpose of the WUR than I can.
The clear strands are fiber optics, transmitting light from the center bulb the the various levers and blower indicator.
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Old 11-30-2007 | 05:25 PM
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Old 11-30-2007 | 05:32 PM
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The WUR reduces the control pressure on the air valve, which in turns richens the air/fuel ratio. As the car warms up, the WUR returns the control pressure to normal and air/fuel ratio returns to normal.

And it's located in front of the intake spider, next to where you add the oil.

Dan
(edit) Jim's right, I assumed it was a K-Jetronic car.
Old 11-30-2007 | 05:35 PM
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Is your 1980 a Euro spec CIS or a USA L-jet ?? makes all the difference in the world. If in doubt post the vin number...
Old 11-30-2007 | 05:39 PM
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this one helped me out
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Old 12-01-2007 | 01:50 AM
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cis
Old 12-01-2007 | 02:18 AM
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The name of the Warm Up Regulator is a misnomer. It is really the heart of the system and does more than affect fuel pressure when the car is cold. For there there are two other components - a cold start injector and the auxillary air valve that are resonsible for warm up conditions. The cold start valve is an electronic injector located on the front of the plenum. When the engine is cold the cold start injector sprays a little gas into the plenum to help the car start. The auxllary air valve also located on the front of the engine has a big intake hose and another output hose going to the front of the Plenum. It is connected to the ignition and contains a heater which slowly closes an air valve. When the car is cold the auxillary air valve is open and extra air is fed into the intake causing a higher idle. If you want to make your car run like crap when it is cold, turn on the ignition switch long enough to heat up the auxillary air valve and then start the engine. The idle will be low and the car will run rough.

Inside the WUR is a heater attached to a bi-metal piece. The heater is connected to the ignition and as the heater heats the bi-metal strip it changes the pressure on the metal diaphram. This is the warm up part of the WUR. There is also a vacuum line connected to the WUR. The vacuum line adjusts the gas pressure in response to the throttle. Changes in gas pressure are critical to the operation of the system. The greater the pressure the more gas is allowed through the injectors. One of the reasons the CIS system is so responsive to the throttle is the direct injection to each cylinder and the ability of the WUR to respond to demand from the throttle. Where the 80s electronic systems run at 30 lbs pressure the CIS system runs at 75 lbs pressure. More pressure greater response.

There is a post somewhere in the Internet about tuning the WUR. It involves installing a screw to tune the bimetal strip. The factory method is to hit the body of the WUR in a special place with a hammer to tune it. I have not tried either method. The diaphram in the WUR is very thin with a very small hole. Even the finest particles of crap or dried gas can cause the unit to stop working correctly. They can be disassembled, cleaned and made to work again.

If you can afford the gas the CIS system is the best perfomance injection system ever made. It is simple, reliable and almost additive to drive.

For a more detailed discussion check out things written by Jay Kempf.

Dan the Pod Guy.



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