Martin, There is only one section in my book that deals with High Control Pressure, and we are "ASSuming that", without the use of pressure gauges. Here it is: Symptom: Cold control pressure high Warm control pressure high System pressure normal Rest pressure normal Possible cause: Restriction in the return line from the Control Pressure Regulator. Defective Control Pressure Regulator To distinguish between these install a replacement return line on the Control Pressure Regulator, allowing the fuel to flow into an approved fuel container. If the Control Pressure drops, then repair/replace the return line. If the control pressure does not drop then replace the Control Pressure Regulator. If this doesn't fix the problem then you need to buy a fuel pressure guage and take some readings. Have you replaced the fuel filter yet?? ALWAYS keep a fire extinguisher nearby when working with the fuel system. Dave Sontos vin 02573 ----- Original Message ----- From: "Martin Gutkowski" <webmaster@xxxx> To: <dmcnews@xxxxxxxxxxxxxxx> Sent: Monday, February 11, 2002 5:18 AM Subject: [DML] Control Pressure Regulator/Twin Turbos [long] I drove about 600 miles with Rich's CPR > in my D, and it progresively got more and more difficult to start, and > ran more and more roughly while warming up. Until one evening when the > car wouldn't start at all. It wouldn't even fire on a single cylinder. > On examination, the air flow sensor was extremely stiff to depress. When > I loosened the Control Pressure line (the one from the top of the > metering head to the CPR), the metering head plunger moved freely again > and the air flow sensor loosened up (petrol leaked from the loosened > line unsurprisingly).