My 06 has had the PO 148 code & engine light on for 70,000 miles. I`ve taken it to two dealers. First one said my engine was bad ( remember that was 70,000 miles ago) The other dealer looked at it about 5,000 miles ago & said I needed a new fuel pump.Not lift pump, injector pump. My smarty says high pressure I thought at first my smarty was throwing a code but I`ve run it with & without it. Now my question is this, what could it be? It doesn`t seem to hurt anything but I`m tired of the light being on. Sorry if I make someone mad but this type of service is one thing that is hurting dodge`s sales. I feel that if it were a ford or gm somebody could fix it. Maybe I need to drive an extra 100 miles & go to a third dealer. I`m just sick of dealers who don`t know how to fix their products.

 

try clearing the code and see if it comes back instantly or if it is intermittent. if intermittent it most likely the fca if instant it could be the fca or rail pressure sensor. the fca is $115 from genosgarage.com the rps is $216 change the fca and if still have code get a rail pressure gauge and see what it does. the rail pressure gauge uses the rps so if it is bad the rail pressure gauge will not work properly. the ecm sends a modulated 5 volt signal to the fca for pressure control if you unplug the fca valve it will peg the 30,000 lb rail gauge. usually if the fca does not get signal to lower the pressure it works the prv valve and ruins it after a short time. since you have that many miles on it i do not think you have this problem

 

P0148 High Pressure Common Rail (HPCR) Fueling Error Checksum

 

Before you go any further, and spend even more money on parts you may not need, re-torque the injector tubes, which will cost you no more than a couple of hours of your time. I had the same code coming up, and this fixed it for me. The dealer I first took it to wanted $750 just to test it, before any parts would be replaced,I laughed at them, and drove away.
I replaced the PRV, FCA,and Rail pressure sensor to no avail, and was ready to start looking at my injectors, when I read about this fix, and had absolutely nothing to lose by trying this, and whadda' ya' know, no more P0148
Good Luck to you, I was at my wits end, and this totally fixed it.

 

Thank`s for the replies. I ask the dealer teck if there was a rail pressure sending unit & he said no. I didn`t ask, but my first thought was if it doesn`t how does the cpu know what the rail is doing. If I look on the rail is the sending unit obvious? Oh, the light come on within a mile or so after I clear it. Kingey, can you explain to me why the tubes needing to be re-torqued could cause this? You`ve got my curiosity up. One more hint. Sometimes just driving down the road at a steady speed I have no power & it smokes black smoke if I push on the petal. Turn it off & back on & it runs fine. This happens about once a week. Thanks again for the help.

 

With the rail running at anything up to 23000+ psi, it is important that there are no places where pressure can be lost, as then the data that the ECM says it should be giving, and the data that the rail pressure sensor (we most certainly do have one, it's the unit on the rail that has 2 wires plugged into it) sees is different due to a leak of pressure, then your truck will throw the P0148 code.
The injector tubes transfer the fuel from the rail, into the head, and to the injectors and work on a taper fit, and if the collars that hold them into the head are not torqued down correctly then the tube is not seated fully in the injector and you lose rail pressure. I discovered this when I installed a rail pressure guage....I would struggle to push 13000psi at WOT, when I should have been pushing 23000+.
All the info you need to try this is either on this forum, or on Cumminsforum.com......it's worth trying, as like I said, it costs nothing, all you need is a decent torque wrench, and a few standard wrenches and sockets, plus a couple of spare hours. At least when you have tried this, it is one more thing you can cross off your list.
Another thing to look at is your oil level....is it too high on the stick, or does your oil smell like diesel?...this is a sure sign of Diesel in your oil, which points to injector issues, the reason I mention this, is you say you sometimes get black smoke, which again, can be a sign of injector issues.
To clarify all of this, I am by no means any type of expert on this subject, I just spent many hours researching my issue, and this is what I discovered was the fix for me. YMMV, but I still say it's worth trying to retorque your tubes as it is free, and simple enough for anyone who is even slightly handy with a wrench to do.

 

good point kingey. but with the new info he just gave us i think he needs to get a gauge first. loose tubes will not cause this problem. it is starting to look more like a fca or cascade overflow valve. loss of signal to the fca produces high pressure and no smoke intermittent low pressure produces what he has

 

Thank`s for the good information. What is a fca? I`m going to torque the tubes but it will be as long as a week before I can do it. As far as fuel in the oil, that has n`t been a problem.

 

I would still say not to buy anymore parts before you try re-torquing....I had pretty much identical symptoms as yourself, my truck would even cut out for a second while driving, and then run as normal, all caused buy loose injector tubes.....I try to look on the brightside about the money I spent on parts I did not need....at least I have spares (all bar the PRV which has a core value) if those parts fail in the future, and best of all, the dealership never got a penny out of me
oh yeah, FCA = fuel control actuator, its the thingy that the wire's go to, on the back of the CP3 injection pump.

 

been fighting this code for two years. i can go weeks without throwing this code or it can happen twice in one week. i lose power and blow black smoke- shut truck off and restart and she is fine. fca,prv and rail pressure sensor has been replaced. injector tubes have been re-torqued- months later i installed new 60hp injectors and torqued tubes correctly. i have spoken to many people about this code including todd at tc diesel. says it is not the cp3 and not the cascade overflow valve-which i was thinking of replacing. my rail pressure readings are within spec at idle and while driving while doing an in flight test with my buddy's scanner-the only problem is the scanner is never hooked up when the code is thrown to see what is going on

 

I finally talked to a shop ( not a dealer ) that has fixed this before. He said he has had three people with this problem that had to get a dealer to flash the emc. So now I have a list of things to try. I`ll try the cheapest first & move down the list. Thank all of you for the advise. I`ll let you know in a few days if or which fixes it.

 

excellent. keep us posted

 

Now I know what the fca is. I changed it about a month ago. It`s just a solenoid that turns the fuel on or off. This lets the key kill the engine instead of pulling a cable.The dealer wanted $600 for it. I got mine at Cummins for $100.

 

i jinxed myself last night by posting to this thread. havent experienced code po148 in a month-until this morning on the way to work and on the way home from work! lost power blew black smoke each time- shut truck down and restarted-then all good-just like the past two years!

 

banyon it is not what you think it is. it recieves a modulated 5 volt signal from the ecm to set the pressure on the cps. with no signal to the fca you will have max rail pressure. you can unplug the fca and start the engine and it will imediately peg the 30,000 lb gauge and stay there. the modulated signal lowers pressure to desired setting.