Attention: TDR Forum Junkies 
I've been having an ongoing issue with low power, poor fuel mileage, black smoke, and high EGTs.
Today, I checked my lift pump fuel pressure (at the input to the injection pump) and found, after the engine was warm, the idle fuel pressure was 15psi (idle fuel pressure was only 5 psi when the engine was cold) and the 2500rpm (WOT) fuel pressure was 22 psi. Both are a bit lower then the factory manual states as the minimums (idle should be between 17 and 22 psi and WOT should be between 25 and 30 psi). I then "pinched" the fuel return line as specified in the factory manual and at idle the fuel pressure rose to between 26 and 29 psi.
As a result of this I have a couple of question. Can a 2psi low fuel pressure cause all the problems I mentioned?
I'm going to replace the fuel filter and the overflow valve(I believe it is the original) just to make sure they aren't the cause but any other suggestions would be appreciated.
Other info. The fuel filter is about 9 months old with about 3000 miles on it;however, I had the same problems even when the fuel filter was new.
Boost tops out at 32 to 36psi but the turbo spools up really fast and EGTs also rise very quickly. Injectors (75hp) are about 1 1/2 years old, lift pump is about 2 years old, air filter is about 1 year old, #10 fuel plate is set at mid range, AFC is mid range, star wheel position is unknown. Tested intake system to 20psi and now leaks were observed.
Today, I checked my lift pump fuel pressure (at the input to the injection pump) and found, after the engine was warm, the idle fuel pressure was 15psi (idle fuel pressure was only 5 psi when the engine was cold) and the 2500rpm (WOT) fuel pressure was 22 psi. Both are a bit lower then the factory manual states as the minimums (idle should be between 17 and 22 psi and WOT should be between 25 and 30 psi). I then "pinched" the fuel return line as specified in the factory manual and at idle the fuel pressure rose to between 26 and 29 psi.
As a result of this I have a couple of question. Can a 2psi low fuel pressure cause all the problems I mentioned?
I'm going to replace the fuel filter and the overflow valve(I believe it is the original) just to make sure they aren't the cause but any other suggestions would be appreciated.
Other info. The fuel filter is about 9 months old with about 3000 miles on it;however, I had the same problems even when the fuel filter was new.
Boost tops out at 32 to 36psi but the turbo spools up really fast and EGTs also rise very quickly. Injectors (75hp) are about 1 1/2 years old, lift pump is about 2 years old, air filter is about 1 year old, #10 fuel plate is set at mid range, AFC is mid range, star wheel position is unknown. Tested intake system to 20psi and now leaks were observed.
