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somethings wrong with the 6.7 swap

4K views 27 replies 10 participants last post by  TylerLtr 
#1 ·


I finished the install of a 2011 6.7 engine into my 2006 ram 3500 5.9 using the 5.9 ECM and the 6.7 injectors. This is what happens when I start the engine. The engine runs real rough and smokes to high heaven. I put about 3000 miles on the engine before I pulled it to go in the 06 and it ran perfect. I'm at a complete loss, If any one has any clue as to why it would run like this please feel free to advise. Thanks
 
#3 ·
Does it do it when you give it more throttle or after it warms up? IIRC the 5.9 ECM with 6.7 injectors was an issue at idle or when cold, I can't remember now off hand but I'm sure someone with direct experience will chime in soon.
 
#4 ·
I think it is supposed to get better when the engine warms up, but I've been afraid to let it run more than a minute or so in case something else was wrong.
 
#5 ·
I have run the rpm up to about 1500 and it smooths out considerably but I could feel it still missing a little bit. I think I'll take it out tomorrow and drive it to see what happens.
 
#7 ·
I haven't gotten any tuning yet, till I figure out if this thing is gonna work. I plan on getting EFI live I'm pretty sure I have all the sensors right but if one wasn't making a good connection would it cause this rough running,
 
#8 ·
Well I decided to drive the truck to see if it helped, couldnt even get out of the driveway. I was standing there listening to the engine and it suddenly dawned on me that it was starving for air. I thought maybe the S&B filter was too small so I took it off to let the turbo suck air straight in, to my amazement there was paper towel stuck in the turbo inlet. I had stuffed it in the intake tube to keep out dust and it got pushed down the tube out of sight. Engine still rough and smokey but after about a mile it cleared up, no smoke, purring like a kitten at idle. Still a little rough when first cranked but I'm hoping EFI live will fix a lot of that. I was super careful about getting everything right while doing the swap, but just plain forgot about the paper towel, I think it sucked some of it through the engine but I dont see how that coiuld hurt anything.
 
#9 ·
you big dunder-head!

haha...seriously though, i'd imagine tuning would likely clear up whatever other running issues you have...this is an interesting swap...6.7 engine, 5.9 ecm, and 6.7 injectors...and a second gen style turbo...pretty cool

was the motor blown in the 06 previous to this, or did ya do it cuz ya could?
 
#10 ·
I bought the truck in 2010 with 48,222 miles and a dusted engine, dodge voided the warranty because the guy never changed the air filter. I was robbed, i had to pay a whopping $800 bucks for it. So I just got around to putting an engine in it. I was spooked from all the horror stories of the 5.9 injectors trashing the engine so reading MoparProuds 6.7 swap post I decided to give it a try. The exhaust manifold is 2nd gen the turbo is a Fleece S463.
 
#15 ·
I was spooked from all the horror stories of the 5.9 injectors trashing the engine.
Probably should have done a little more research, there isn't enough difference between a 5.9 and 6.7 injector to be worth mentioning. The results of a failure is still the same.

Other than the 6.7's are easier to find, not a lot positives going that route given the inherent issues with the 6.7 design. Hard to make a case about it being an upgrade, unless the 5.9 had a hole in the block or broken crank a rebuild would have been a better investment.
 
#12 ·
Thankfully most of the paper towel is still intact, I only cranked the engine 4 or 5 times with a total run time of less than 5 minutes at idle. When the towel made its way to the turbo it just stuck in the impeller and stopped it from spinning so if any did get by it was just a very small amount
 
#16 · (Edited)
The main reason I used the 6.7 was that I could get one with low miles, 56k for 4500 with a trans and tcase. All the 5.9s I could find had 100k plus and cost 6500. Having read in numerous articles that the 5.9 injectors started failing in as little as 60k and all of the 5.9 engines that I checked on had some degree of blowby. I could not see spending 6500 for a high mileage 5.9 with blowby and the chance that the injectors were on the doorsteps of failure thereby needing another 1500+ for a set of reman inj that most everyone says to stay away from. Would a 5.9 been a much easier install, certainly, but the mathematics ruled out and I had money left to make a few upgrades. I catch hell all the time for hammering on the shortcomings of the 5.9 cr but the bulk of the evidence is hard to ignore. I bought the truck with a trashed engine, virtually every thing was toasted, engine, turbo, injectors.
 
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#18 ·
I catch hell all the time for hammering on the shortcomings of the 5.9 cr but the bulk of the evidence is hard to ignore.
And rightly so, the alleged shortcomings were self induced in most cases with a lot of help from the manufacturer. Aside from the random hard parts failure, the design of the 5.9 and its longevity are solid. Totally incomprehensible how anything BUT that can be derived from the available information.

It is has been proven beyond a doubt that 6.7 subject to the same fuel quality and filtration level the 5.9's suffered from for so many years WILL result in the same outcome. For every problem injector problem found there are 10 that did not have the issues noted, it was all subjective to maintenance and attention to what went into the tank. Sorry, but that is the real truth.

A 6.7 swap is not a bad deal given the circumstances you found, the cost is probably close to what a rebuild and replacement of all the parts on the 5.9 would have been, given you have a good base to work from. If the block or crank or rods were hurt then it becomes a different deal.

However, now you have to deal with the inherent issue of the siamesed cylinders and head gaskets in a 6.7. While it can be addressed, it is still the weak spot that cannot be fixed.

While 45k is not many miles you should also consider the 6.7's can use up to 5 injection events in their programming as opposed to the 2-3 in a 5.9 setup. Depending on how it was used, driven, and maintained that 45k could be easily comparable to 150-200k in a 2 event system.

On the other hand, you may have gotten a low miles engine that has been maintained correctly that will be a good option. Not so much that you got any better equipment, but, rather because you got lucky. Once it is tuned correctly and you have another 200k on it, that question will be answered. :)
 
#17 ·
A 6.7 will get a leaker nozzle just as easily as a 5.9. All depends on quality of water separator and dirt filters used. And whether the owner is running bonehead overpressure RPs

The new 5.9 injectors are the same metals and quality as the 6.7s, just as rust resistant and wear resistance.
The 6.7 injectors do wear out, wait until you have to replace a set of those, sticker shock.

The later 6.7 trucks come with a quality filtration system.

The junke yards have been stripped of the rebuildable 5.9s
 
#19 ·
Cerb, man I didnt mean to offend you, I was just relating what I had read and heard from owners of the CR 5.9s and why I chose to go with the 6.7. I have a 95 12v and it is solid as a rock, The only thing wrong with the newer 5.9s and probably the 6.7s is the govt emissions crap that make them more prone to failure. I have a 6.0 powerstroke that I think is the most hated engine made if you listen to a lot of the owners, but I love mine. Thats not to say that I dont cuss it a blue streak when it breaks, but since I do all my own work I can fix it fairly cheap, and since I replaced all the crap that the govt and ford put on them that made them unreliable it has been golden. I might have made a mistake by using the 6.7 but like you said, time will tell and the option of rebuilding 06 5,9 was not viable as it was totally bombed.
 
#22 ·
Cerb, man I didnt mean to offend you,
Not offended at all, just chatting. :)

In the end it is your truck and you are free to do as you please. I sincerely hope it works out and you have no issues. Would not want you to have issues to prove a point, that is just to self absorbed. ;)
 
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#21 ·
I didn't know about the Siamese cylinders, but that shouldn't affect me since I wont be racing, sled pulling or building high HP. I'm just looking for something that cranks every time i turn the key and keeps doing that for mucho miles, and has enough power to pull a stock trailer of horses and hopefully gets good enough fuel mileage that I can afford to drive it. Lol
 
#23 ·
Well,I thought I would give an update on the 6.7 swap since I FINALLY have some good news. From the very first crank the engine run extremely rough and smoked like crazy, even after I cleared the intake of the paper towel that I had stuffed in it to keep out dust. I purchased EFI live tuning from ATP and the first tune I received made the engine start and idle perfectly but as soon as I touched the pedal it started the same rough running/smoking event. After a couple more tunes the engine only had to warm up for 5 min or so before running smooth, but when driven it ran good till I let off the pedal to change gears then it would go right back to the rough/ smokey idle. I was on the verge of setting fire to it and just driving my 6.0 PSD. After numerous trials I realized that every time I drove the truck the engine acted/ran differently. So I sent my ECM off to get checked since the scan guage kept showing only 11.7 volts and the A/C compressor wouldnt kick in. Also during this time my brand new batteries went dead twice after the truck sat for 4 or 5 days. The microprocessor was burnt out in the ECM. Yesterday I installed a brand new ECM and VIOLA from first crank the engine idles/ revs perfectly with no smoke even when first cranked. I've driven the truck several times and the engine runs great no problems at all and I havent even reinstalled the EFI tuning on the new ECM yet. I can finally see the light at the end of a very long, dark, frustrating tunnel.
 
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#25 ·
I used the 5.9 harness, almost all of the plugs will work on the 6.7. This 6.7 is a hoss!!
 
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