WRU/Cold Start???

[BOCNasty]

I am new to the Porsche car and I'm having problems with the car starting cold. After it's warm it runs and starts fine. Looking through the forum I've seen posts about the WRU/Cold start. Where is it? and can i repair this myself? I have rebuilt engines before so mechanically i have the tool to do a lot. Thanks for any info. Pic's of the location would help also.!!!

[Scott R]

You can test the CSV by disconnecting the plug to it and then trying to do a cold start, it will be VERY difficult to get it running with it out of the loop. Then try another with it connected and see if the engine at least catches, if it does it's probably working.

The WUR is also very easily tested, hook up a set of CIS gauges and pull the plug on the WUR, start the motor and measure the cold control pressure, should be something like 23PSI given about a 60deg F garage temp. Then plug the electrical connector and watch for the pressure to rise, it should hit around 50PSI or so, check the archives for the exact numbers.

The WUR is replaced easily by removing the 14mm supply line to the fuel distributor, and the 12mm supply line, then two allens that bolt it to the runner.

The CSV can be replaced by removing the air boot, and the throttle body from the air box, reach over and remove the fuel line, the tow allens and your there, a mirror is also helpful here.


If you search here this topic is covered many times.

[sushinav]

It's probably not recommended, but I managed to disassemble my WUR on my old SC. By cleaning it and reassembling, I cured the problem. May give it a try before buying a new one, they are a bit spendy. Oh, and it's on the left side, top, near the intake manifolds. It's a silver rectangle about4"x2x2 with fuel lines running into it.

[ianc]

If you're just having trouble with cold starts, it's much more likely that you're having an issue with your Cold Start Valve (CSV) rather than the WUR (Warm Up Regulator). Trouble spots for the CSV are the electrical connection on the starter solenoid, and the thermotime switch on the left hand chain cover.

See Jim Williams' excellent CIS page for more info:

http://members.rennlist.com/jimwms/CIS/CIShome.html

HTH,

ianc

[Scott R]

Originally posted by ianc
If you're just having trouble with cold starts, it's much more likely that you're having an issue with your Cold Start Valve (CSV) rather than the WUR (Warm Up Regulator). Trouble spots for the CSV are the electrical connection on the starter solenoid, and the thermotime switch on the left hand chain cover.

See Jim Williams' excellent CIS page for more info:

http://members.rennlist.com/jimwms/CIS/CIShome.html

HTH,

ianc

That's in fact how I test the CSV, I disconnect the yellow wire at the starter since it's easier to get to,

[BOCNasty]

Thanks for all the information i'll let you know how it turns out!

[BOCNasty]

Don't know if this has anything to do with my problem, but i noticed while driving the car around the Temp display in the dash does not move. I know the engine is hot but could this have anything to do with my cold start problems?

[Sunroof]

I am having difficulty with my WUR and have been shopping around for prices on a new WUR versus a rebuilt unit. The difference betwwen the two are about $100-$200, and both offer a one year warranty. Having never cracked one of these open, what goes wrong with these units and just what do they do in the rebuilding process?

I have the 1973.5T first WUR used by Porsche and it cannot be rebuilt. I can opt for the next model with the retro-hose kit.

Thanks
Bob

[ianc]

Bob,

If you are a bit handy, you can modify your WUR to be adjustable. Takes a couple hours, saves you a big chunk of cash, and you'll know your fuel pressures are spot on. Do a search here,

ianc