I disagree completely. I'll refer you to the Porsche factory manual for the proper name of the device. Furthermore again, 99% of the time its a warm pressure regulator.. its main function is NOT a warm up regulator as I define main.

Besides "WUR" and "Dizzy" are just the silliest sounding acronyms I have ever heard. I simply cannot use them without feeling well, silly.. so I'll continue to put them in parents so "Porsche people" understand what I am talking about.

Thanks for the clarification on the vacuum port however.. makes sense I guess.. So while I was right, if you apply negative pressure to the bottom it will pull the diaphram downward, I was wrong because the spring pushes it as far as it will go.. so I apologize for that mis-information.

Now I can set it per the manual as soon as I figure out how to apply the proper vacuum to the damn thing.. more test equipment to buy.. great. Actually, I'll probably use my manual method (actually, now we all know it is a Porsche method thanks to a fellow pelican!) as I am pretty sure its spot on anyway and compensates for age of the motor and all the rubber hoses and "thingys"...

I'll try that.. good idea.. DUH.. should have thought of that. I think I'll make mine adjustable too while its out...

Thanks for all the help and I hope this will help someone out in the future! My guess is with vac my manual method will STILL be spot on..

thanks jp.
the BOSCH k-jet book i have ONLY refers to it as the WUR. it also spends almost 2 pages explaining its function during the WARM UP period. (not yelling, just emphasizing).
although....i have a future horizons bosch CIS book that calls it a WUR but it also says it is called the CPR.
if the main function of the WUR was not controlling the pressure, then there would not be the need for that chart above with all the temp/ pressure numbers.
anyway, i really dont want to make a big deal about it......anymore;)
if you want copies of the BOSCH book i can send them to you, in fact, if you want the whole book i will email it.
let me know.

i also was confused about the atmosphere port at one time.

The reason why the charts are there are because warm up is not static. Warm running is static so a single # is required. Its that simple.

I will follow the Porsche manual.. It is after all a control pressure regulator which is a much more accurate definition than a warm up regulator.

Oh and I have the Bosch manual but if you want to scan it in for me sure.. send me a pdf ;)

I have been told in email that my tests are not complete.. that its imperitive to test warm running pressure... I responded back that its a WUR and it doesnt matter what is happening after the car is warm.

;)

He is correct of course but after testing dozens of these control pressure regulators I have NEVER seen one correct on cold and off in warm run... but as soon as I fix the damn thing (needs a new heating coil. parts ordered) I'll find out and post results.

Where did you source individual control pressure regulator parts? Thanks!

Brian

i would have given you a heating coil, chances are the bi-meatal spring may be worn out too. in other words, i would not waste/ chance the money that the rest of the WUR is still good.

i have a bad WUR that i can heat the bi-metal spring but it does not move/bend.

Terminology for WUR.........
 

JP,

After a series of messages between us, I think you are really hanged up with this term. Plus the fact that you don't understand about control and system pressures makes me wonder about your work. You don't adjust the control pressure by tweaking the MIXTURE!!!!!

The fact that you did not install the CIS fuel gauge correctly the first time you hooked up tells something about your experience. Now you're telling me (PM) that you have the best procedure in adjusting a CIS air mixture really caught my attention. I'm an avid CIS user and really wanted to know.

Maybe you just have discovered a novel procedure in CIS trouble shooting without using CIS fuel pressure gauge and correctly adjusting the air mixture with a big vacuum leak.........deserves recognition. But I'll wait until the time you make your car run and follow your footsteps. I'm not saying you're wrong just a little bit skeptical at this time. Only time will tell about your discovery. Good luck.....
Tony

Hasn't calling911 just outlined another way to try to find the correct mixture setting when warm, and then used the "knocking the plug" technique for getting the thing started from cold? Many of us have been doing this for years. I think it assumes that the warm control pressure is OK for the engine, and this seems to usually be the case, as it's the coldcp that seems to go out of spec, or maybe more correctly a worn engine requires a lower ccp for starting.

Some of you may remember that I had a WUR problem this fall, and found that I could no longer get a good wcp that was in spec. I had to go about 1 bar lower than spec both for cold and warm, and then the engine ran beautifully. When I used my usual technique for setting idle mix, I found that what seemed best equalled JW's recommendation of 3.5% CO, which I confirmed w/ a loaned LM-1 that measured the equivalent A/FR.

Some have suggested I have a massive vac leak somewhere, but none was found by me or 3 mechanics.

During testing of 3 WURs we found that 1 w/ the correct cps seemed to run way too lean, although admittedly this was for a lambda controlled engine, and that 2 used ones never got above 1 bar, which was the cold cp setting we were using.

This was the first time in 20 yrs w/ this car that the existing wcp seemed to be other than what was required.

Well now you get to hear a story.. so I was racing a 1984 VW GTI with the SCCA.. road racing.. not sissy autocross.. just kiddin.. sorta..

anyway.. I ran into a guy who used to drag race a GTI.. he said he had built his OWN intake manifold and some other crazy stuff.. also he went thru HUNDREDS of injectors to find 4 perfectly matched injectors and would sell them to me.. I was ALL OVER THIS.. this is the KEY to getting the MOST power out of a VW or any CIS motor actually... So I go to meet him at his place.. while talking I see this box FULL of "WURS"... DOZENS.. I say.. DUDE! WTF? He;s like yeah I collected these over the years.. "want them"? LOL.. Im like HELL YEAH..

so there you are.. I sold them with the car.. WHAT AN IDIOT.. I had 4 of them I would use to race with depending on the temperature and humidity.. when it was really humid Id run pretty lean.. when super hot Id run rich.. blah blah.. you might ask.. why not just adjust the mixture?? Because the spray pattern would get messed up that way.. I tested the injectors at all different pressures and found that when I changed the pressure using the mixture adjustment it would screw it up.. dont know why and may have been a bad unit I had but it is what I had.. My GTI was sick fast.. especially right after a rebuild.. and it was 100% stock per the rules.... just had the head sliced to min. and 5 angle valve job etc...

Sorry.. had to tell the story..

As for all the critisism I have been getting.. yeah I AM hung up when people call things the wrong thing.. just annoying.. so what? Im annoyed... Does it bother you that calling a control pressure a regulator a warm up regulator annoys me? If it does why?? Tell me about your relationship with your parents.. did you have any trauma in your childhood? LOL.. just kidding..

Some advice.. if you think Im stupid.. pitty me.. cuz attacking me will get you no where.

Anyway.. NOW I AM REALLY going to go check my warm run control pressure... I will report back.. AS SOON as I get the warm up coil in place.. I thought about doing it with the bi metal strip out.. I think it would be accurate.. do you? If so I'll check it.. I frankly have never looked to see if the strip is putting ANY pressure on when its hot.. but am told it puts none on.. if thats the case let me know and Ill test and report back.. if you dont trust me I'll take pics :) But I never lie.. I gave that up about 15 years ago.. doesnt work long term. ;)

BUt even if its off.. well. Im still correct about the "WUR" actually being a CPR.. baahahaha.. . :) 99% of the time it controls control pressure.. but its a wur.. lol..

Just for those that dont know CIS.. here is what would happen if your control pressure regulator was unstable or off substantially WHEN YOUR CAR IS WARM:
Your throttle is metered by a INGENIOUS plate which controls your fuel to air ratio MECHANICALLY.. This plate goes up and down as air is forced thru it by the sucktion of the pistons... (in computer controlled cars we call this a "fuel map") as the pistons suck more air the plate moves up and releases more fuel.. the CONTROL pressure is like having a EXTREMELY precise spring on this plate the limits how fast and how far it moves up and down.. in other words.. if you DID have a spring on it it would move say 1" with X amount of air being flowed by it.. then put a stronger spring in its place (ie the control pressure is WRONG) the metering plate would only move 3/4"... thus you;d have more air than fuel. This is why increasing control pressure leans the car... Also, the speed at which the plate moves is controlled hydraulically by the control pressure regulator.

This spring effect is happening ALL the time and MOSTLY when the control pressure regulator is NO LONGER acting as a warm up regulator.. in fact warm up regulator is not even correct.. at cold start its a warm up control pressure regulator or a WUCR. LOL..

So to me, its just silly to call it a wur.. its MUCH more important than a WUR..

So yeah Im hung up on it.. but I'll let it go after the beatings and sarcastic remarks continue on a little longer here.. I've never been one to go with the flow..

BTW, while it describes its function as controlling pressure, the Bosch Technical Manual for CIS K-Jetronic Basic refers to the component as the Warmup Regulator.

Okay.. finally got the heater rebuilt and installed the "wur".

After setting the the pressure using my without pressure gauges offering It is dead on both cold and hot. @ 17c it shows 1.6bar and once the bi metal strip is heated it reads 3.1 bar. Both are right in spec per my Porsche manual for the 1976 911s. Per the manual, this is with no vacumn.

This is after completely knocking the pin out of the "wur" and driving it back using my method.

Also.. the heater repair worked perfectly (you can see details and a pic in a thread I started on repairing the "wur")..

The heater repair also solved my surging idle as expected (once it got to be winter it started).

Just thought Id add this for anyone needing to adjust pressure without gauges.

I have used the method described by Calling911 and it worked for me (I have tried others WITH gauges also, but with far less result).

This one has given me the best result.

My car is a 1983 EURO SC with NO lambda.

Three obeservations:

I prefer the blipping of the throttle as described by JP over the "push lightly on the allen wrench" of Calling911 (What you guys call a light beer we call limonade, so my point being that there are different opinions on what light is ;o)

Disconnect the Deceleration Valve. Mine was slightly caput and it messed everything up. So disconnecting it solves that problem. You do not need it when doing this procedure.

Messing with the allen wrench on the fuel distributor dumps more fuel then you would expect so make sure you burn it all off before making any conclusions. I think it takes more time then you think to burn off the excess fuel it dumps. A short squirt around the block is better IMHO then just revving the engine.

Hope this helps anyone. My car is back in full health after being completely off for quite a while.

Thanks to the original creators of this thread.

Michel

Thanks for the feedback..

I didnt realize I said to push on the allen wrench.. I'll have to reread that... My initials are JP and my "handle" here is calling911 so maybe there is some confusion there.. I know I mention blipping... you have to in order to clear things up after an adjustment.. anyway.. I'll just leave my little redneck adjustment stand as is.. again, its more for people with slight problems like a minor air leak that cannot be found.. better to have a P car on the road then parked in the garage.

When continuing to tune my mixture I noticed the following (note all my remarks are based on experience of 1 car)

Following Calling911 advice I came close to getting a good enough mixture but I still was left with a minor hunting at cold. So i manipulated my mixture to the extent where also that went away.
In doing so I noticed that the difference in mixture between perfect idle at cold and slight hunting is very minor. You would think that you need to turn the allen wrench 1/4 turn a time but I found that not to be teh case.
1/8 or even 1/16 was the difference that made it for me.

After doing that I hooked up my LM 1 and found that my AFR is at 11 at start-up and then moves to around 14. I see 13.9/14 AFR when fully warmed.

Hope this helps someone.

If anybody is reading this I have found that on my SC EURO 1983 the ideal AFR ratio at IDLE is around 13.20 AFR (which is about 3,5% CO).

More responsive no stumbling at pick-up etc.... Ofcourse your mileage will suffer a little and the green left wing tree huggers might object.

Michel

Hey just wanted to post a thanks for this, had problems cold starting as the fall temperatures where dropping and I used this to set up my control pressure regulator and it cold starts better now.

I own a '74. Its original CIS has a TPS (throttle position sensor) for acceleration enrichment. I up-graded to a complete CIS off a '79. It has a vacuum controlled WUR which serves to enrich the mix on acceleration. Which setup provides for the best 'hard' acceleration? Should I install my old TPS onto my new throttle body? Or should I stick with the vacuum hose on the '79 WUR to handle enrichment for acceleration?

I would stick with the later design. CIS will never provide the impact of Carbs or MFI since the cams are so mild.

Use the WUR you mentioned.
The TPS on later CIS only disables the lambda emissions system that leans out the CIS somewhere around 2/3 throttle open on up so it effectively richens the mixture a little bit according to throttle position.

CIS is a 100% mechanical fuel injection system. Electrical devices like a throttle position sensor have no effect on the actual fuel injection system pressures.

Mechanical CIS is controlled by system fuel pressure which should remain constant all the time and hydraulic control pressure changes in the fuel head.
You have the mechanical air flow sensor plate pushing the control plunger upwards in it's cylinder with fuel metering slits in the side as the engine revs up and sucks in more air and hydraulic control pressure pushing down on the top of the control plunger keeping it from going all the way up in it's cylinder exposing too much of the fuel metering slits and flooding the motor with wayyyy too much fuel.

With todays E10 fuel in the USA the original non ethanol tolerant o-rings in the fuel head are going to break down and start to leak. This is going to eventually happen and it's just a matter of time before the motor starts running rough or miss on one or more cylinders at low rpms from leaking rubber o-rings installed on the outside of the fuel head control plunger cylinder.
There's one large o-ring in the bottom of the inside of the control plunger cylinder too.

After market ethanol tolerant rubber fuel head o-rings and rubber diaphragms used in aluminum fuel heads are available in fuel head rebuild kits from a couple places. One place that has them is Welcome to salvox! - salvox

Sometimes they sell on ebay for little bit lower prices than directly from their website so an ebay search may save some $.

while you are correct, the early CIS systems had a mechanical throttle position sensor to adjust fuel pressure for enrichment. It was eliminated in 1975 in favor of the vacuum actuated unit the OP has. This Web site has a lot of good info: 911 CIS Primer - Index

Nice description.

Good to know.

I had a the early CIS in a 74. Never noticed any running issues related to TPR when the pressures and CO% were correct. That includes hot Texas at around 800ft to 10F overnight then up to Pikes Peak (14,100ft). Gas is between E5-E10 around here.