Truck is an 02. Alison trans.
At 196k I replaced the injectors/lines/glow plugs. Ran the valves because I was there. Installed a FASS 95GPH Lift Pump along with one of their suction kits. Also installed the CAT filter adapter, bought EFI/tunes from Idaho Rob. Also installed an EDGE CTS2 to keep an eye on things. Truck did not like the pressure from the uncut lift pump spring. Cut one loop off of it, pressure at the fuel filter head went from 11 down to 3-4psi. Was assured by FASS that the pressure is not important in a stock truck, just that there is volume at the CP3 pump.
Truck ran great. Over the 77k miles since doing the above truck has ran great. Have replaced all the fuel filters several times. Have noticed that the pressure at the filter head had dropped dramatically..and is never consistent. One trip it never gets over 1 psi, next trip it never drops under 2 psi.
Getting ready to do some maintenance, checked codes. P1093. Fuel filters have 7k on them. Truck is in the garage, will be changing them shortly. Have had 3 sets of filters on it since installing the pump etc. The low pressure at the filter head started with the first set still in the truck, which led to the first change. Still low pressure so just ignored it.
Once I saw the code the other day I changed the display so I could monitor both the actual rail pressure and the desired rail pressure. Driving at 60 with the cruise on both are the same. Climb an incline on the cruise they both climb up to just under 21k in harmony. Climb an incline (cruise off) and both remain in harmony until I stuff the pedal to the floor. Actual pressure will not get over 17k while the desired will be at 21k or so. Back off and they are in harmony again at 21k or so. Also noticed that when stepping off the throttle from speed the desire rail pressure will often be higher then the desired pressure for a short term. Amount varies, one time drp will be at 7k, the actual will be 7.4k. Next time drp will be 6k, actual will be at 16.5k.
So...does all the above just point to dirty filters? Planning on cutting the old filters open to see what they look like when my filter cutter shows up (never loan tools). Truck has the original regulator and CP3 pump in it. Since getting the truck with just under 100k on the clock I have been dumping 6 or so ounces of Stanadyne diesel additive in it every other tank. I know many consider this "snake Oil" but my buddies employee that went thru the trans was a diehard D-Max guy and he swore by it so...
At 196k I replaced the injectors/lines/glow plugs. Ran the valves because I was there. Installed a FASS 95GPH Lift Pump along with one of their suction kits. Also installed the CAT filter adapter, bought EFI/tunes from Idaho Rob. Also installed an EDGE CTS2 to keep an eye on things. Truck did not like the pressure from the uncut lift pump spring. Cut one loop off of it, pressure at the fuel filter head went from 11 down to 3-4psi. Was assured by FASS that the pressure is not important in a stock truck, just that there is volume at the CP3 pump.
Truck ran great. Over the 77k miles since doing the above truck has ran great. Have replaced all the fuel filters several times. Have noticed that the pressure at the filter head had dropped dramatically..and is never consistent. One trip it never gets over 1 psi, next trip it never drops under 2 psi.
Getting ready to do some maintenance, checked codes. P1093. Fuel filters have 7k on them. Truck is in the garage, will be changing them shortly. Have had 3 sets of filters on it since installing the pump etc. The low pressure at the filter head started with the first set still in the truck, which led to the first change. Still low pressure so just ignored it.
Once I saw the code the other day I changed the display so I could monitor both the actual rail pressure and the desired rail pressure. Driving at 60 with the cruise on both are the same. Climb an incline on the cruise they both climb up to just under 21k in harmony. Climb an incline (cruise off) and both remain in harmony until I stuff the pedal to the floor. Actual pressure will not get over 17k while the desired will be at 21k or so. Back off and they are in harmony again at 21k or so. Also noticed that when stepping off the throttle from speed the desire rail pressure will often be higher then the desired pressure for a short term. Amount varies, one time drp will be at 7k, the actual will be 7.4k. Next time drp will be 6k, actual will be at 16.5k.
So...does all the above just point to dirty filters? Planning on cutting the old filters open to see what they look like when my filter cutter shows up (never loan tools). Truck has the original regulator and CP3 pump in it. Since getting the truck with just under 100k on the clock I have been dumping 6 or so ounces of Stanadyne diesel additive in it every other tank. I know many consider this "snake Oil" but my buddies employee that went thru the trans was a diehard D-Max guy and he swore by it so...
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