Nathan

I know that rebuilt units can be purchased; can a person rebuild his current warm-up regulator? Is the best option to purchase a rebuilt unit?
Thanks<
Nathan

IslandmanPA

Check WUR over on pelican parts forum. There is a rebuild thread!

theiceman

Hey Nathan do you KNOW this is the problem ? One of the guys here did have a problem with his , put a fuel pressure guage on the line and tapped some spot with a drift and fixed her up ? apparently you can rebuild it if you " tap it in " too far. But others can comment on this !

Nathan

Not 100% sure,; however, everything I read about spits and pops at start-up when colder, and an idel that revs itself, seems to point to this. I'm not sure I fully understand your process with the fuel pressure gauge.

IslandmanPA

Long write up on pelicanparts.com, 911 technical section, search at bottom of page under WUR!

theiceman

If you can get your hands on a CIS manual I would read this over first before ordering parts. The warm up regulator maintains a higher fuel pessure while cold IIRC , as the car warms up the fuel pressure is lowered by the WUR . There is a " cold pressure" that must be within a certain spec when the engine is cold. tapping the little piston in a little while the car is idling can increase the cold fuel pressure. I am playing hockey tonight with the guy who did this and will ask him to chime in. The only reason I mention this is that it is an expensive part to be guessing with . vacuum leaks can also cause your problem BTW.

ice

IslandmanPA

http://www.forums.pelicanparts.com/s...&highlight=WUR
is very helpful in diagnosing problem and how to repair!

IslandmanPA

http://forums.pelicanparts.com/showt...&highlight=WUR

first one didn't work!

theiceman

oops ... miss spokr . i meant lower control pressure on cold engine ... islandman's link is a good source ..

psalt

Nathan,

No, the WUR is not rebuildable like a carb, the parts are not sold OTC. You really need to have someone who understands CIS test the system pressures before pointing the finger at any component. Some of the WUR's are NLA, it is a shame when someone who has his wired crossed hacks up a perfectly good unit chasing his tail. What model 911 do you have and when was the last time the ignition and mixture was properly set ?

Paul

Nathan

It's a '77. I do not when the timing has been checked or the mixture. Other than idle at start up in the cold, it runs and starts fine. When the temperatuer outside is warmer, the symptom doesn't occur. I plan to check the timing sometime soon. I did just replace the plugs, rotor, cap, set the valves, and fuel filter. The wires have less than 500 miles on them. Fouled plugs caused me to do a tune-up. It seems to run fine now. The cold idle symptom was occurring before the tune-up. I do know that I have a bit of an exhaust leak, but that would only cause backfires through the exhaust primarily under decel.

Brett San Diego

Do not touch a thing until you do proper diagnostics, unless you don't care about cost. It can get really expensive really fast replacing CIS parts ***** nilly.

First order of business is to check fuel pressures (primary system pressure, cold control pressure, and warm control pressure) then get your timing, mixture, and idle set properly (as already mentioned) by someone with an exhaust gas analyzer and who knows what he is doing.

good luck,
Brett

psalt

Nathan,

If you plan on keeping the car and working on it, buy Probst's book on Bosch injection and a CIS test gauge. In the meantime, use an unlit propane torch to test for vacuum leaks around the injectors and runner sleeves. Any vacuum leak results in less deflection of the air sensor plate and a lean mixture. Porsche chose an inferior method to retain the injector sleeves and the sleeve orings, not the injector seals are probably toast by now.

Paul

Nathan

Thanks for the tip, vacuum leaks were the next issue to touch on my schedule.

theiceman

Nathan

Here is one procedure I found , I am sure there are others.

http://www.nichols.nu/tip726.htm

here is a procedure for making it adjustable..

http://www.pelicanparts.com/techarti...warmup_reg.htm

I would not attempt this unless
1. You have run the diagnosis with a pressure guage
2. You have determined the WUR to in fact be the fault
3. were going to buy a new one anyway.

Good luck.