rammv

Changed oil and fuel filter this weekend. After normal prime 4-5 times to fill fuel canister it fired up but rail pressure was at 4 -5,000 at idle not normal 6- 7,000. No fuel in oil. Truck runs fine, starts up a little slower but not bad no smoke at start up and normal smarty smoke when you get on it. Noticed last week the exhaust note changed at idle a little bit kind of like the idle was down about 250 rpms. PRV valve,FCA or Lift Pump? Thanks for any idea's

Chryco Psycho

the injection pump will draw fuel through the dead lift pump but it is hard on ot , I would be checking the lift pump to make sure it is doing its job 100%

Polaraco

Agreed

Did you use a quality fuel filter? Too fine a micron can cause that drop too. If that is the case, you need a stronger lift pump

Frankly, I would use the finer filter and put in a better lift pump.

no_6_oh_no

FCA would be my guess. Try running a mixture of Power Service and 2-stroke oil for a while and see if anything changes.

Obviously, verifying fuel pressure at the IP is a good start. The in-tank pumps are pretty reliable and if it was weak you should see a power loss and excessive EGT's\black smoke when you get after it.

rammv

Thank you all. I undid the banjo bolt on the prv valve and under idle fuel comes out. Is this and indicator it is bad? I will try and get a fuel pressure gage to check pressure. How do I check to see if the fca is bad.Btw I use a baldwin Fuel filter pf 7977 I think is the number.

no_6_oh_no

No, you can't chekc the PRV that way. The line coming under the banjo is open to the injector return circuit, that needs to be isolated from the PRV.

The PRV is in the bottom of the well under the banjo. Clean it good with carb cleaner and blow it dry. Start the engine and look for fuel showing in the well. Run the motor up to 2000 rpms for a couple minutes and check again for fuel. If you see any fuel then the PRV is bad.

There is no positive way to tell if the FCA is good, only installed and functioning will any issues show. Its one of those wear items that just need replaced occasionally.

rammv

Thank you very much for the insight. Will check this weekend the right way, but while I was driving home yesterday engine died on me.It did this once before and it turned out to be the quad where it plugs into the rail pressure sensor,sure enough I unplugged and plugged back in and truck started up and rail pressure was back up where it should be and this is a new wiring harness I bought about 2 months ago.I forgot from last time the symptoms,figured it was a nwe wiring harness should not have happened again.Thanks again.

no_6_oh_no

Sorry, saw Smarty and ignored the rest of it. Yes, if you have ANY mods that plug into the data port, the MAP, or the injection harness ALWAYS disconnect them first to see if the problem goes away. They are electronic pieces and subject to the same failures as the rest of the truck, just easier to isolate.

2006RedRam

Are you running a rail pressure gauge

rammv

No 6, thats cool appreciate all the help. Red Ram it's the quad x2 race with pod. have it set to pressure tunes but only use it for that once in a while. mainly use it for the rail pressure gage.