Cm 2350 surging at high idle

[Rawze]

The fuel rail on them rises to pressure "X" then the pump bypasses. After the pressure drops off from use of the fuel down about 200-300 psi or so,.. the fuel pump kicks back in and re-pressurizes the system. It is known as a bypass-charging system. This cycling of the pump and pressure has 2 effects. It causes slightly higher engine load when it kicks in, and as it falls off, it effects injection slightly.

I would imagine that as the engine and systems get older,.. or if you went from 3 pistons to only 2, this fluctuation could get more pronounced. - I doubt there is a complete cure, as it is designed to work that way. Even so, it should be quite subtle, but i would imagine that contaminents, clogged lines, screens, and.or filters, or perhaps moisture or a bit of air in the fuel would make it worse.

Just my own thoughts, I don't own one.

[Platinumpete]

Mine does not surge or stumble at all with cruise on works perfectly but when I hit brakes to slow and then accelerate will ocasionally stumble then is fine. Is doing that now 4 or 5 times a day. Have good power. I'm wondering if accelerator switch at pedal may be failing but that doesn't answer the occasional surging at idle.

[Platinumpete]

Rawze, what your saying makes sense but we're talking about a truck with only 335000 on it a 2014, new parts would really have to be crappy, I say that and yet I just replaced the turbo. I long for the old 3406 cat days.

[JMBT]

Platinumpete: I long for those old days too brother and I would gladly go back in half a heartbeat! Believe it or not I have talked to many O/O's on the road with 2250's and 2350's that have already been inframed by 335000. It makes me feel like I am on borrowed time at 605K!!!

[Billdozer2]

(05-21-2017 )JMBT Wrote:  Platinumpete: I long for those old days too brother and I would gladly go back in half a heartbeat! Believe it or not I have talked to many O/O's on the road with 2250's and 2350's that have already been inframed by 335000. It makes me feel like I am on borrowed time at 605K!!!

Same here. I'm only at 465k but I have heard of other owners on my account having rebuilds done with half my mileage. One guy had a rod punch a hole through the block. I think it only had like 150k on it. Makes me sick thinking about the time bomb under my hood. I try and take care of it. Changing oil every 10k, keeping boost pressures below 20psi. But I know that day will come and I am not ready.

[mmssvv]

(05-22-2017 )Billdozer2 Wrote:  

(05-21-2017 )JMBT Wrote:  Platinumpete: I long for those old days too brother and I would gladly go back in half a heartbeat! Believe it or not I have talked to many O/O's on the road with 2250's and 2350's that have already been inframed by 335000. It makes me feel like I am on borrowed time at 605K!!!

Same here. I'm only at 465k but I have heard of other owners on my account having rebuilds done with half my mileage. One guy had a rod punch a hole through the block. I think it only had like 150k on it. Makes me sick thinking about the time bomb under my hood. I try and take care of it. Changing oil every 10k, keeping boost pressures below 20psi. But I know that day will come and I am not ready.

Don't worry guys,breathe deep.We all are in the same boat but think about the good part of all this crap.After 10 or 15 years the drivers will comment how good engines we got now lasting 400-500k.Xaxaxa.:)

[Platinumpete]

I keep mine well serviced but I don't baby it. I'm a texas only truck and the speed limits here average 75 so I run 78 all the time my average day is 700 miles and I get home every night. I still have 3 yrs payments to paccar the next big repair bill paccar will be paying cause they'll own it again and I'll go find me one of those 3406s.