i dont know what to do here fuel problems
- Thread starter mch646
- Start date
I can assure it's not a tuning problem cause the same tunes run great on his tow rig and he just says to buy bigger sticks and a new cp3and don't mess with each part individually which I would do if I had the money but it's not an option for me right now
Sorry, I checked your thread at lunch today but didn't have time to reply.
I would try a FPR before a cp3... Like Chris said call Dimitri he probably has one laying around you could try. If he doesn't Try calling Trent (EPR). Heck I have one that I would loan you but it will take a week to get to ya. Also I have heard of guys running 2-stroke oil to help free up sticky FPR's for what it's worth... Just the cheap walmart 2 stroke oil nothing fancy.
I would try a FPR before a cp3... Like Chris said call Dimitri he probably has one laying around you could try. If he doesn't Try calling Trent (EPR). Heck I have one that I would loan you but it will take a week to get to ya. Also I have heard of guys running 2-stroke oil to help free up sticky FPR's for what it's worth... Just the cheap walmart 2 stroke oil nothing fancy.
Ha I would but pat is helping me with one after a bottle test tomorrow I drove up to dimitri last week for a returned and the dsp5 but this problem was there before these tunes. Anywhoo he is building 3 trucks ATM which I am excited to see this year it will be a nice surprise he's running 2 at drags and has a nice twinned tow rig ha I don't understand how he does it tho and the oil is dummy cause I run that ever 5 tanks or so to help quiet it down. And its OK dude don't worry bout it
OK just an update here y'all changed my fpr with a brand new one and its still the same general symptoms idle Psi is actually higher now and under wot its 12-14k depening on tune so I guess lucky me gets to change the injection pump unless there is something else I am missing ps the port on the passenger side of the engine where you check fuel vacuum that leaks constantly and the lift pump is at 8 psi
super diesel
<<<< Under Pressure
Do a search for " Mod to turbo intake horn " stared by Super Diesel.
Post #102 shows how to do the FPRV shim mod.
Post #102 shows how to do the FPRV shim mod.
super diesel
<<<< Under Pressure
Sure it will. It can only bleed off pressure so fast. That means that when the injects stop using the fuel they want, or sharing the fuel with the all the injects and FPRV it ALL goes to the FPRV and sensor on the junction block. The reg on the cp3 can only react so fast to shut down the pressure and all the pressure built up already needs to go some where because the injects arn't using it any more. This is the reason for spikes when the throttle is chopped off the best I can explain it. These have been know to be a problem in the past with draining off precious fuel pressure and I don't suspect the issue will be getting better over time unless there shimmed. May not be the problem or all the problem. But one less thing to go wrong in the future if addressed. This is trouble shooting stages that must be taken to find the root cause. Your eliminating a possibility and it may or may not suddenly cure it.
super diesel
<<<< Under Pressure
Its in the valley right down in front of the turbo and on top of the air intake Y bridge. The FPRV is pointed at the passenger side fender off of the junction block. some steel lines (return fuel lines) are banjo bolted to the output side of it. This will have to be disconnected to remove it for the mod. Well, you don't have to remove it but it's a bit trickier doing it that way.
super diesel
<<<< Under Pressure
Try this. While looking under the hood, unhook the FPR and look for any leaks at the injector fittings or at the rail end plugs. Make sure everything is buttoned up good. Did you say you did a bottle test and checked for no fuel in oil? I know you said your injector rates were reasonable, but you need to rule more stuff out to get to the root.