[Johnell]

I have a 1977 280Z. I have replaced all fuel lines, fuel injectors, fuel pump, fuel pressure regulator, fuel filter, and checked out the fuel relay switch. The problem is that the fuel pressure after the filter is reading over 80 psi. The engine will crank over for several seconds then die, but the pressure never changes from the high pressure reading. I can find no blockage in the fuel lines and going back to the tank. Is there anyone who has run into a similar problem? I would appreciate the input.

Johnell

 

[johnh240]

Just for clarification, are you using a 'T' fitting at the filter to check pressure, or are you just disconnecting the line and deadheading the gage in? If it is deadheaded at the gage you WILL read a very high pressure (ie engine not running, just pressure from pump). If you are measuring w/ a T and engine running/starting if pressure goes that high then something is acting as a block to the return pressure line. Almost sounds like the supply and return lines are reversed. If the lines were reversed to the fpr I don't think it would allow any reverse flow and could act as a blockage causing a 'deadhead' situation and the high pressure build. Might want to just connect the supply directly to the return with the T and pressure gage and see what kinds of pressure you get just on the lines and pickup. If the pressure drops down to around (guessing here) 20lbs or so then that would show that the problem was in the fpr or the lines to the injectors. I have seen the gallery pipes on the injectors clog also, which in the right place could restrict return fuel flow.

 

[Johnell]

t-fitting

I have a T-fitting attached just as the FSM instructs. I will connect to the return side to see what the reading is there. Thanks for the tips.

Johnell