Another fuel pressure question

[Andries]

Hi.
When I switch the car to the ON position the fuel pressure goes up to 42psi while the fuel pump is energizing. As soon as the fuel pump switch of again the fuel pressure drop to 22 within 5 seconds. After that it start to drop more slowly. (2psi per minute) What type of valves is there in the fuel system and how can I test them. I see the fuel pypes are steel so I cant blank them off.
Thanks

 

[G Winter]

Does the car start ok after allowing the pressure to drop ? If not you may have bad injectors. If it starts good I would say your fuel pump is the problem.

Glenn

 

[Andries]

Starts fine as soon as the pressure goes up again. When hot it cranks for about 2-3 seconds and when cold about 5 seconds.

 

[G Winter]

Ok starting that quick should rule out injector leak. I am not sure how the pump works , if there is a back check or what. I know on my high milage GM cars I turn on the key and let the pump quit running before cranking.If I don't I have to crank for 4 to 7 seconds before they start. I assume I am losing fuel pressure on them.If you have no leaks in connections or lines I am not sure it is a concern, I have been driving my Riviera with 227 k on it for about 60k in that condition.

Glenn