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Truck is "Dead in the water", Codes are all fuel related, did my CP4 Pump just fail?

3118 Views 55 Replies 19 Participants Last post by  biodiesel
Hey guys, figured I would share my latest misadventure with you so at the very least maybe we can all get a kick out of it. Yesterday I was driving my 2016 Ram Ecodiesel down the Interstate. I just passed a semi in a light snowstorm, when suddenly I hear a ding and the check engine light comes on. hmm, couple seconds later get another ding and bright red symbol saying something like "service electronic fuel throttle". hmm, I quickly realise the engine is no longer running, my speed is dropping and the transmission can be felt shift gears down slowing me. All I see is a big "Freightliner" emblem getting really big in my rear view mirror. Perfect timing. So I quickly turn on my hazards and get onto shoulder avoiding the bird being thrown at me and air horn blaring. "sorry buddy, not intentional". So I quickly decide to see if it will restart and allow me to limp to the next exit about a mile down the road. Crank, crank, crank..... nothing. Hmm, I decide to grab my OBD Link and see what we got. All fuel system related codes. (See attached pic for codes). Hmm, you know i wonder, there is that CP4 recall I still have not heard anything about that is not good. Tow truck comes and takes me to the dealer, thankfully i was still local and not on one of my typical long distance trips. In route I called and warned the dealer, giving her the codes and my fears of the CP4 recall, she said they would watch for it and see what they find. Upon getting there, she says yep, there is a recall for that on your truck. So good news is if it is that you should be covered, bad news is parts were supposed to be ready first quarter this year, but current estimates are now 3rd quarter this year. Oh wonderful. They wont be able to look at the truck till thursday of next week so we shall see what we find. I will update you when I learn more. Ofcourse I work out of my truck often several hours or more away nearly every day. I need my truck to make a living. 3rd qtr is really not an option. And ofcourse since i bought the truck at another dealership becouse their salesman wasnt able to find me the truck i wanted for 2 years and i gave up waiting on him, they wont give me a loaner. only to the customers that got it from them. even though all my service on each of my vehicles is done there. nice policy. Dad recently totalled his spare truck so i cant use that. Fortunately father in law is letting me use his new tacoma. but I think i have already put more miles on it than he has. I cant keep doing that until 3rd qtr. Not to mention, I am a bigger guy, I look like I am climbing into a clown car getting in and out of that thing. lol. Now honestly i have not had all that much for issue given the amount of driving I do. so, i cannot complain about that. I will be patient for now and see what we find perhaps i will get luck and not take as long as feared. So what are your thoughts guys? you thinking the same thing, CP4? Little back ground truck has around 157,000 miles and the original engine was replaced around 53,000 due to a failed main seal dumping the oil out at once. Or so i learned after buying it. lucky me. I do most of my own preventive maintenance. I change fuel filters every other oil change so that would be roughly 14,000 miles. i do oil at 7,000 -10,000 miles. OEM Fuel Filters every time. I also religiously use a fuel additive for lubricity and other benefits since i owned it. last 2 tanks i let get down to 1/4 & 1/8 tank due to availabilty of local fuel stations at the time. upon restarting the truck the engine cranked and cranked for a long time before firing. making me swallow my stomach. but all other starts in between and since. it fired right up. never done that before. at first i feared bad fuel, but as i said ran fine and started fine every other time and this was 2 different stations 100+ miles appart. Coincidental or not truck is at 1/3 tank now sitting at the dealer lot. I forgot to mention tow truck driver said it did start for him when he was unloading it at the store. go figure. Sorry i am long winded, but wanted to get it all down. I will update you guys as i learn more.
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A fuel additive isn't going to help the lift pump. The purpose of a fuel additive is to add lubricity to the fuel, which would improve the life of your CP4 pump. The lift pump just needs to stay cool by keeping the fuel level above the 1/4 mark.

The lift pump, similar to the water pump, is a wear item. The idea behind preventative maintenance is to replace these parts before they are known to fail. This isn't easy to do without taking lots of data. I made my 150,000 - 175,000-mile preventive maintenance recommendation based off a reliability-shaped curve. At 150,000 miles, we begin to see lift pump failures on the EcoDiesel. This tells me that the lift pump has reached full-service life at 150,000 miles and the reliability will decrease as more miles are accrued.
The lift pump in my 2016 GC started whining about a week ago...it will be getting replaced this week, as I have no intention of running it until I need a tow truck.
The vehicle has 91000 miles on it so I am somewhat baffled by the early demise, but at the same time, not all that surprised .
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Yup, that would be an early failure. Do you oftentimes run your fuel down below 1/4 tank?
I personally do not, but I bought it used about a year ago, and although I know the original owner, I don’t know his habits .

I also have a 2016 grand Cherokee with a 3.6 in it and oddly enough that pump went out at 60,000 miles.
I did not hear any pump noise with that one so it came as a surprise
I was lucky as it literally stalled as I was pulling into work so I did not need a tow .
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