High Fuel Pressure

[KingTut]

Hey guys, I've been having a problem with my 99 Ranger running rich. I took a fuel pressure reading today and got 0lbs with KOEO and 54 lbs while idling. Now I read in the tech library that 30-40 lbs is the normal operating range. What would cause the high fuel pressure reading? Thanks

 

[bobbywalter]

bad fpr/blocked bypass

but iirc you should be returnless, and that is a bit low actually.

low fuel pressure can cause issues.

 

[Sasquatch_Ryda]

Non Flex fuel is 64psi ( + or - 8psi)

Flex fuel is 55psi ( + or - 8psi)

 

[KingTut]

Thanks sasquatch for confirming the correct numbers.

 

[modelageek]

Hey guys, I've been having a problem with my 99 Ranger running rich. I took a fuel pressure reading today and got 0lbs with KOEO and 54 lbs while idling. Now I read in the tech library that 30-40 lbs is the normal operating range. What would cause the high fuel pressure reading? Thanks

like they said you should have 64 plus or minus.........you have an issue with the koeo pressure............can you hear the pump for a few seconds when you are koeo.........you should get to proper fuel psi koeo within a few cycles of the key........I would change your fuel filter to begin with

 

[KingTut]

I've tried getting a reading multiple times with KOEO but it doesn't measure anything. I have the flex fuel motor so I beleive I should be running at 55 +-, so the fuel pressure is there. Went out this morning to analyze the truck while running and I noticed that when it is cold it runs amazing. There's no issue with idling but when it warms up that's when it acts up and idles like it has an oversized cam. It shakes back and forth and sounds like there's a miss.

 

[modelageek]

Hey guys, I've been having a problem with my 99 Ranger running rich. I took a fuel pressure reading today and got 0lbs with KOEO and 54 lbs while idling. Now I read in the tech library that 30-40 lbs is the normal operating range. What would cause the high fuel pressure reading? Thanks

I've tried getting a reading multiple times with KOEO but it doesn't measure anything. I have the flex fuel motor so I beleive I should be running at 55 +-, so the fuel pressure is there. Went out this morning to analyze the truck while running and I noticed that when it is cold it runs amazing. There's no issue with idling but when it warms up that's when it acts up and idles like it has an oversized cam. It shakes back and forth and sounds like there's a miss.

flex fuel is 47-63 so you are good koer......you need to listen for the pump when you turn the key to koeo and see if it comes on for a a few seconds.............check your air filter and intake for blockage...... If I was you I would start bringing all the maintenance up, clean MAF, TB, IACV, fuel filter , air filter etc etc.......also how do you know it is running rich....did you check for codes? do you have any codes?

 

[KingTut]

Modela, the things that I have replaced are: plugs and wires, coil pack, fuel injectors, MAF sensor, IAC valve, DPFE sensor, EGR valve, PCV valve, TPS sensor, both upstream O2 sensors, air filter and getting ready to change the fuel filter. Going to go listen for the fuel pump after this. I've cleared out the codes that were previously stored, drove it down the road, and got p1132 and p1152 when I got back. I then cleared those codes out and drove it down the road to see if it would throw them again... It did. I'm getting a consistent p1132 and p1152 codes. I'm not sure if the rich condition is whats throwing these codes or some other underlying problem. I know it's running rich because I'm getting a strong fuel smell from the exhaust and black smoke at idle. Oh and thanks for your help. I appreciate it!

 

[KingTut]

Ok, so I went out and listened for the fuel pump to to turn when turning the ignition on. I could hear the fuel pump run for approximatey 2-3 seconds. I also hooked the fuel pressure guage back up and this time I got a reading of 30lbs with KOEO. All of this was done after the vehicle had been driven and warmed up. The readings that I took and got 0lbs KOEO were when it was cold and sitting for a long period of time. Not sure if that as anything to do with it? I'm going to go out tomorrow morning and see if I an get a pressure reading when the vehicle is cold.