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Greeting Saabers
The 74 has a hard hard time starting-also was fouling plugs quickly. Running rich/ black plugs after a few minutes. and even black soot at the tailpipe.
So, attached a fuel pressure gauge, cleaned the plugs and fired it. Would not fire unless the throttle was open slightly.
With simply the temporary fuel pump feature (when key is turned to ignition) engine not started- the gauge advanced at twenty- then slowly goes down to 10psi. I turned the key off and on again(for a second hit from the fuel pump) and the gauge advanced to 20 immediately. After cranking it for a moment, and opening the throttle, the engine fired and ran- the fuel gauge now at a consistent 30psi.
The exhaust stunk(running rich) I then adjusted the fuel pressure regulator to 28psi- and the engine began to idle smoother.
Upon turning the car off, the fuel pressure gauge shot down to 20 quickly- then to ten psi a moment later- ultimately going down to 2 psi a few minutes later.
I tried to start the engine again-even giving it the boosts from the fuel pump, prior to firing it, and it will not start. I then packed up.
Question, what is the normal fuel pressure amount for djet, after shutting off engine? Should it not hold the pressure- if so what psi? The gauge not is at 2psi. If I turned the key to ignition, the fuel gauge immediatly shoots to 20psi, and after starting- remains at a constant 28psi.
What are the proper reading amounts for when engine is off, and also after the boost when ignition on? How quickly should the pressure decrease?
Thanks for any help.
I have the gauge hooked up between the fuel rail and the fuel pressure gauge as the service manual indicated.
posted by 107.55.3...
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