Reiver

The wur on the 930-10.... 911.606.105.09 is different from the US in one function (that I know of) and mine seems to be not working.
When you accelerate the euro wur has a pressure/vacuum line that allows the AFR to increase under hard throttle....mine is not presently doing that (AFR on board).
My afr is set to 13 @ warm idle...will cruise at 13.4/13.7 but when I stomp it it jumps to 14 or slightly higher rather than dropping as it should.
Which line (Steve or anyone with the knowledge) should I be checking?
The one to the fuel head.
The line to the small plastic vacuum.
The line directly behind the air filter.
The car starts fine cold, high idle kicks in...no issues hot or cold start.
It also runs great but I want to see that afr drop on acceleration to about 13 for a sweet spot.

Thanks....not to bright wur owner.

Reiver

Ok, after jumping all over the web I got what I needed.
I have no response when I remove the top vacuum line (next to the elec. connection) and cannot induce a reaction (richer afr) using a tube.
I do have vacuum in the appropriate hose as I can feel it creating v.
This leads me to believe I have a bad wur.

Mondrian

What is wur?

Reiver

Pretty much my question when I started messing with it and its functions.

Warm up regulator on all CIS system Porsches....
controls pressures etc. in the fuel system.
Called the 'control pressure regulator' in the Bentley manual.
On the non lamda year cars it also controls air fuel ratio whilst driving.

theiceman

maybe its just designed to stop the afr from leaning out ?

did you try a few runs with that line disconnected to see what happens ?

Reiver

I was testing wrong.
The wur I have is the same for the 78/9 pre lamda SC's and all of the row cars thru '84.
Unlike the early non L wur's it has a double diaphragm and the vacuum line to control AFR IS the horizontal nipple out of the base...the top line is atmosphere. (older wurs had this reversed)
Thru Howard F (guy that built my lump) he hooked me up with the 'only guy in the world' to redo wurs.
Had a good phonecon with him and he explained the nuances of dif wurs.
Going to send it to him for testing and exchange...said he has about 1200 cores on hand.
It's been an education.

theiceman

i have the same wur being a 78 had no issues to make me go check it though.

are you having any symptoms ?

Reiver

The only thing it does not do is enrich the AFR under load.
In truth, if I didn't have the onboard gauge I'd think everything was jake...car runs great but that's also because I run a fat CO. I am leaving hp on the table tho so want it to do what it is supposed to do.

theiceman

personally i dont think you are leaving any hp on the table. id be very interested in what the wur rebuilder says.

Reiver

I'll let you know.