Lowest Fuel pressure = 50 psi

[iBoostDSM]

As the title says I can't get my fuel pressure under 50 psi. I just installed a Walbro 255 fuel pump and a SX racing afpr. I turned on the pump via DSMLink to adjust the pressure and the lowest I could get was 50psi. What's up, is the afpr bad?

 

[drooseph]

Are you trying to adjust the afpr with dsmlink? you should try setting to afpr to the lowest possible setting manually via a screw or knob on the afpr. And how sure are you this was a 255 not something else?

 

[iBoostDSM]

I was turning the knob on the top of the afpr, and I checked the numbers on the fuel pump and it's a walbro 255. The knob is so far out that when I keep turning it the fuel pressure doesn't go down any farther.

 

[drooseph]

I was turning the knob on the top of the afpr, and I checked the numbers on the fuel pump and it's a walbro 255. The knob is so far out that when I keep turning it the fuel pressure doesn't go down any farther.

could be wrong here but I think you need to tighten it in order to decrease the pressure. I have only ever installed these not set them to anything.

 

[iBoostDSM]

Ok I'll check it out now, I was loosening it and it was going down so I figured that was right.

Ok, I tried tightening it, turning the knob clockwise and it just kept going. And I was also way off with the pressure, it doesn't go below 57psi. Kind of a big difference. This may help I noticed the fuel pressure before a had the 255 on would shake a real lot. The engine wasn't shaking a lot but the gauge was shaking in maybe about a 10 psi range. I'm beginning to think it's bad.

Also I have never tried starting the car because the pressure is so high.

 

[iBoostDSM]

Found out what it was....it was a bad gauge.