I have a problem with my 911 CS 1978/1979 with starting and running when the motor is cold.
After the motor has been warmed up, it runs smoothly and also starts easely, but still has very few power.
The timing of the ignition has been set pefectly.
The car has the original CIS (K-Jet) inhection system.
When pushing the sensor plate of the CIS fuel injection a little bit the motor runs fine stationary
and the revs may be increased without having detonations at the inlet manifold. (Fortunately there is
a valve build into the air filter housing!) When the motor is cold, it turns out that the control
pressure is too high (2.7 bar, which should be the pressure when warm). The heating element of the
WUR has about 20 Ohm, so it is not burnt through. Probably I will have to search for a new WUR. Following
the original Porsche Repair Manual it seems that the WUR has been changed at Jan 1979 from model nr 911 606 105 05 (Bosch 0 438 140 045) to nr 911 606 105 06 (Bosch 0 438 140 069). The differences are in control pressure when motor is cold (1.8 versus 1.35 bar) and when warm (2.9 versus 3.25 bar)
Currently my CIS system has got the first of these two. My question is if I can change the WUR to the newer model or has the WUR stricly related to the fuel distributer?