Why does my 1999 Infiniti Q45 starts then dies after 5 seconds?
I took fuel line off regulator and started it. Loads of gas came out of line. Replaced it and removed return line. Again started it to find hardly a dribble coming back from regulator. Strongly suspect fuel pressure regulator but, don't want to but it if that's not the problem. Bruce
Cars & Trucks - Infiniti - Q45
Answers & Comments
If the regulator has a vacuum line to the back of it ,check that the line is operational. A good fuel flow before the pump indicates that the pump is moving volume but when a restriction is added ( regulator ) it may be passing the fuel back past the gears in the pump. have a fuel pressure test done on the fuel manifold . If it is excessive then there is a problem in the regulator. However if it is low then the problem may be in the pump.