common rail trucks

[champspa]

I was reading the survey on cr injectors and over 18% have had to replace injectors. is this common place having to replace injectors ? not many seem to have a lot of mileage on the trucks. my old 96 hasn't had any injectors yet at 247k and still runs great . Lets hear it about the new stuff is it worth a poot?Oo.

 

[RDyson]

I don't think the # is that high. You do read about some having problems, but I didn't think it was that many. I have 101k on mine with no problems.



Randy

 

[Mobius1]

ITs like that saying if something good happens to you, you will tell 1 person. IF something bad happens you will tell 10 people. The numbers may not be exactly right but you get the point.

 

[Cattletrkr]

I was reading the survey on cr injectors and over 18% have had to replace injectors. is this common place having to replace injectors ? not many seem to have a lot of mileage on the trucks. my old 96 hasn't had any injectors yet at 247k and still runs great . Lets hear it about the new stuff is it worth a poot?Oo.

Change your injectors out for new/upgraded ones and compare. I'll bet it's not "good as new" anymore.

My opinion on these CR trucks is that they use $500/ea "throw away" injectors. Better than the ones used in the 6. 5L GM, but not much.

 

[HBarlow]

My '06 has almost 222,000 on it with the original injectors and injection pump. I do have an occasional intermittent undiagnosed rough idle but that may be a result of ULSD fuel rather than a design or manufacturing problem with an injector or the HPCR system. Personally, I don't think the CR engines are a problem. Remember, only a fraction of Gen III owners are TDR members and only a few of the TDR members have posted having a problem.



Harvey

 

[GaryOwen]

I have 338k miles on my 03 with original injectors and injection pump. Have had less problems with the 03 than I have had with my 95 which has 297k miles.



Maybe I've just been lucky and my truck may squat tomorrow, but from what I have seen, I would buy a 3G truck again in a heartbeat.



Gary

 

[rbattelle]

I originally created the injector replacement poll for exactly this purpose - to get an idea over time roughly how many people are replacing at least 1 injector due to a failure.

The current results indicating ~19% are disturbing, but remember that the poll is unscientific and doesn't account for the presence of "extenuating" circumstances (such as performance boxes), which may (or may not) inflate the failure rate for non-modified trucks.

Ryan

 

[RailroadJim]

Seems to me when the 03 came out and lasted a few years there were probably fewer complaints and tsb's than any other vehicle i've known, now that doesn't mean perfection but their darn close. The most talked about issues on this website without a doubt are injectors and ball joints (4x4 only) to me that's small potatoes which i haven't even had to deal with compared to vp44 lift pump issues on 2nd gens, kdp, lift pump, door sag, paint etc... on 1st gens all based on doing a search of problems on this sight alone. It's no secret the 3rd gen injectors are not cheap, but usually the two micron filter addition fixes that and cheap, ball joints, not a real big deal just for the front, greasable parts are available. In my opinion it's the truck that has come farther not so much the engine but now you have great power right off the lot with easy plug and play for more. Basically if you keep on top of just a very few issues you should have many years and miles of trouble free service with the 3rd gens Jim

 

[RMalone]

I agree that the injectors could be better. I have had a few problems myself, some of which were no doubt my own fault. I will say though that I have had no problems since adding a 2-mic filter. It does seem that high milage trucks like the previous posters have the fewest injector troubles. These trucks are also most likely to fuel up at high volume truck stops where the fuel is probably better, and do a higher percentage of their miles at peak temps and rail pressures.



I have driven, not owned, 1st gen and 12v and 24v 2nd gen trucks and by far the nicer truck is the 3rd gen, which I do own. Is the 3rd gen as reliable? I guess it depends on which parts were talking about.

 

[DLane]

Remember, only a fraction of Gen III owners are TDR members and only a few of the TDR members have posted having a problem.



Harvey

There are plenty of others having problems too. I just bought a "core" motor from a 04. # 4 piston melted, bad injector. This gentleman is not a TDR member, and did not report it here, but still had to spend the money for a new motor. And this is not the only case I know of. I would say that the 18 or 19% is probably real close to "correct". May even be higher than that as I am on my third SET of injectors on my 05. 1st set I had the truck modded and at 37,000 changed them out as I voided my waranty. Also took of ALL fueling mods. Down to better fuel filtration and strait pipe. 98,000 new set of injectors, now at 110,000 I am already seeing the signs again. Intermitant rough idle, ect. Some of this stuff just does not get "posted" to be found and hashed over. I have 7000. 00 worth of injectors in the last 2. 5 years in my truck, Maybe the originals where because of the fueling box,(I do not think so but maybe) but the last two sets were only run stock, and still went bad with MUCH better fuel filtration than came from the factory. IMHO the 3rd gens are not as reliable as the older trucks. The next step for me is to LOSE the common rail system. For the money I have put into injectors I could(and should have) changed to a mechanical pump.

 

[MickeyMiller]

Would the use of a 'pressure box' (Edge) help the injectors? i. e. Result in fewer injector problems?

 

[rbattelle]

Would the use of a 'pressure box' (Edge) help the injectors? i. e. Result in fewer injector problems?

No, exactly the opposite - shorter injector life. At least, that's what casual observation seems to show.



Ryan

 

[AHolt]

After reading about guys injectors breaking down.

I bought a used set on ebay,sent them to Don

and had them reworked. I did this for no other

reason then piece of mind knowing I had a better

injector.

 

[MA2LA]

After reading about guys injectors breaking down.

I bought a used set on ebay,sent them to Don

and had them reworked. I did this for no other

reason then piece of mind knowing I had a better

injector.

I've been considering the same thing, that way if an injector does go south I have the spares to put in and not have the ruck down fora week.

 

[BothellDiesel]

Third Gen Injectors are garbage. For those of you who have not pulled your injectors for tips or whatever go ahead and swap a couple around to different cylinders. That "fuzzy" memory in the ecm will show a bad injector with a rough idle or in my case the gear shift was shaking like crazy. A contribution test doesn't prove anything. Its good to find a used set like the member above and have someone like Don or DDP put them on a flow machine. If you think you may have an injector problem pull ALL of them not just a couple. You'll be surprised... ... ... ... ... ... ... ... ... . I've had to replace 6injectors this year.

 

[MickeyMiller]

I would be interested in improved reliability and a little more power and potential for improved economy. How would I select replacement injectors? Reworked originals? Or?



TIA

 

[rjrkihap]

6 injectors at $500 a piece!!!! WOW. Does anyone in the after market make a "better than stock" injector that will last? Can the stock injectors be "modified" to make them last? What about injector cleaners, better fuel lubricants, etc? Can bad injectors be reworked and reused?



One VP44 = $1,200 and 6 injectors = $3,000.



Thanks for the info.



Ron

 

[AHolt]

Miller
Find yourself a used set and send them out and have
them upgraded to stage I. You will have everything
you are looking for.
rjrkihap your 99 injectors wont cost that much.
Find a used set have them upgraded, no where
near that price. You can send yours in and have
them rebuilt if you can go without your truck.
I plan on sending my stock injectors to Don
and get a larger set made.

 

[DLane]

MOST used common rail injectors are NOT rebuildable due to damage. I considered this but after talking to the boys at I. I. decided that even for the 5 to 700. 00 that they can be bought for on Ebay, It is just not worth the risk. You can just as likely get six paper weights as six rebuildable injectors. I am very glad that some have gone the Ebay route and been sucessful, just be aware you could be buying garbage. Just remember the last time I spoke with I. I. they were not even offering rebuilt CR injectors.

 

[betterthanstock]

Third Gen Injectors are garbage. For those of you who have not pulled your injectors for tips or whatever go ahead and swap a couple around to different cylinders. That "fuzzy" memory in the ecm will show a bad injector with a rough idle or in my case the gear shift was shaking like crazy. A contribution test doesn't prove anything. Its good to find a used set like the member above and have someone like Don or DDP put them on a flow machine. If you think you may have an injector problem pull ALL of them not just a couple. You'll be surprised... ... ... ... ... ... ... ... ... . I've had to replace 6injectors this year.

Well, the differences in pressure between P7100, at 17400-18900 psi, the VP 44 at 21,800psi, and 26,100 psi and the CP3 at 23,200 psi, (all according to bosch) are not that great to begin with. It surprised me.



After I honed my injectors to 34% higher flow, and verified on the dyno to be right on, I was expecting the MPG gage to show 34% higher. Instead it reads 21% higher. This tells me that 10% less fuel flows thru the injectors than expected. I attribute this to a 10% drop in commanded rail pressure, because the ECM bases commanded pressure and timing upon the power demanded by your right foot. (I do not have a pressure gage, so would someone with one chime in?)

So if the ECM sees a 33% lower load, perhaps it commands a 10% lower pressure (at crusing, not full power). If that is the case, then my pressure has dropped to the level of the P7100, or less, at cruise. Injectors should last longer, due to lower wear, and less chance of cracking.



The pilot injection puts extra wear on the injectors at low speeds and power. (It's not used at high rpm/power).



The fundamental flaw of common rail is the continuosly available pressure at the injector. Thus, a leak that would not matter in a classic diesel, continuosly leaks fuel into a cylinder (even during intake and exhaust strokes) and washes unburned fuel down the cylinder wall into the oil.



A leaky older style injector would not flood a cylinder like that, it would just leak out the same fuel quantity too early, at too low a pressure for proper combustion.