My 89 F150 Is not running as well as Id like to. I have changed out the ECM and its running better. when I drop it into gear it tends to stall I need to know this when the engine is off ignition on the fuel pressure is 45lbs.

Does it need to remain at 45 lbs while running

or what????

I need ECM info

Chris

 

Yes, 45 psi minimum at all times. If its dropping, your fuel pressure regulator is bad.

 

Best I remember, at idle it should go down to around 35 psi due to the vacuum on the pressure regulator.

 

If my fuel pressure regualtor is bad, could that cause my truck not to start up, and the pump not to prime? if not i know for sure that the fp is bad, the relay is good also

 

If you have the 300 six it should be more like 55-60psi.

 

Are You guys talking about the fuel pressure in the rail....My 302 EFI 86 Bronco reads 28lbs in the rail.....Is that sign my regulator may be bad..