ok need some help on this one. Hooked up my buddy's truck, 06 5.9 common rail to my snap on ethos deluxe scanner. fuel rail pressure was 500ish at idle but did go up to around 1800ish at 3000rpms. that doesn't seem like enough to me for a common rail. how much should i have? im thinkin relief valve or fca?? what do you guys think. or is the cp3 on its way out?? He said when he's towing a 6k trailer hes losing power on the hills. but no codes are coming up. Thanks in advance for any help you guys can give me.

 

The pressures you have listed are not enough to even run the engine. Do not think you are getting a true reading on the pressures.

Check the lift pump pressure. Could be the fuel filter is partially clogged or the pump is not supplying enough fuel to the CP3.

 

You should be seeing 6-7k at idle and around 25k at WOT, and if I'm not mistaken you need at least 2-3k just to get it to fire.

 

i thought the pressures seemed low. maybe i'll hook it up and check again. i'll check the lift pump pressure too. I'm used to messin with 12 valves so bear with me on this.