Fuel Pressure

[Jim Burch]

Have over 60 psig fuel pressure.Is there a way to check the fuel return line as it may be blocked? Any other solutions to help troubleshoot the problem ? i.e. fuel pump ? Seems the pump would have low pressure if it was going bad .



Thanks

 

[scott degroot]

These will put out about 60-65 psi of fuel. The fuel system is a returnless system, meaning that it doesn't have a return line to the fuel tank. Are you having some sort of issue??

 

[Jim Burch]

Working on my 97 V6 Fi50 engine. keeps givng me high fuel pressure (well over 60 psig) and trying to trouble shoot

 

[Richard L]

Snoop,.



I suspect that the fuel pressure regular may be part of the fuel pump in the gas tank since there is no return fuel line. If the regulator is part of the pump assembly, the excess fuel pressure drains into the tank and probably the cause of the hard starting problem in the early Gen-1 Sport Tracs.



I am curious as to your different descriptions of the problem. First you say that the pressure is over 60 PSI which is normal, then you say it's way over 60 PSI? I don't know what the exact pressure range should be, but many fuel pumps for injected enginces can have normal pressure ranges that vary by 20 PSI.



...Rich

 

[scott degroot]

Ok well a 97 F150 with a 4.2 is just a weeeee bit different than a ST. What problems are you having that is making you look at the fuel pressure??

 

[Todd Z]

LOL, My st runs close to 75 PSI !!!



Todd Z

 

[Jim Burch]

We keep rupturing the FPR diaphram as this will be the third one once we locate sourse of the problem. When we check with gauge it will peg it all way to 0. It is a big job replacing the fpr and still trying to figure if the pump also has some sort of regulator.Truck has sat for over 18 months so guess next step is to drop the tank. It does have a fuel return line so going to make sure that fuel is being returned to the tank

Any suggestions would be welcome.



Snoop

 

[Todd Z]

Sounds like a pump problem..... The st runs high Pressure normally.... Is yours a job 1 because the job2 and up the regulator is in the tank on the pump...



Todd Z

 

[TRACket Paul]

Todd, see the 3rd post above, not an ST.

 

[scott degroot]

The fuel pump does not have any sort of regulator built into it, it puts out what it puts out and the regulator on the rail does the rest. If the gas in that tank is 18 months old then it needs to be drained and fresh fuel needs to be put in before anything else is done. Old gas can eat away at the rubber components of the fuel system in a heart beat and I have seen it totally destroy the insides of a fuel tank before. While it is possible for the return line to become plugged I have never in my career seen this happen, but I have seen stranger things happen. It is easy enough to check just disconnect the return line from the rail and see if you can blow air through it just make sure to remove the fuel cap if you are using an air hose that way you don't overpressurize the fuel tank. So you have fuel coming out of the vacum line that goes to the fpr right?

 

[EddieS'04]

If the FPR's are aftermarket discounts. I wonder if you are not getting a bad batch from china or india..just guessing..

 

[Jim Burch]

yes the vacum line fills up with gas. Guess that the next project is to drop the fuel tank and inspect the condition of the tank and fuel pump.



Thanks for your suggestions



Snoop