Dodge Cummins Diesel Forum banner

1 - 16 of 16 Posts

·
Registered
Joined
·
14 Posts
Discussion Starter #1
First off, I use this truck for my business as mobile automotive technician. I really haven't done anything with diesels much besides my time in the army. Lately I have noticed a brief hesitation between me pushing the pedal and the truck actually moving. Almost like a brief dead pedal. Well. Today it just bogged down and began blowing grey/white smoke BAD! It also began knocking. Now I know enough to know for a fact it's an injector knock. I immediately shut the truck off and coasted in neutral to safe spot to park and got a tow truck to haul me and my truck back home about two miles. I already removed the valve cover now and have pulled 3 of the six injectors the OHM readings were in spec on all 6, (tested in place.) And have decided to reach out before I pull the back 3 and it just started raining also, so I was forced to cover the engine up and call it a day. I noticed where the turbo mounts to the manifold is soaked, also a barely noticeable spot on the far back cylinder exhaust port, on the top of the tube about 2 inches away from where it bolts to the head. I've read else where that's a sign #6 is stuck open. I've searched and searched but nothing truly stood out to me in my searches. I dont own an injector tester, nor do we have any "decent" diesel shops around that qre able to get me in.being a veteran small business owner that I just started has drained me in start up costs etc so I can't currently afford all 6 injectors or I wouldn't be here, I would simply replace them all. Any advice would be greatly appreciated! By the way all mods were don by the previous owner except for the tune. My diagnostic tablet ( snap-on modis ultra) is sent put for a warranty claim so I dont have a scanner at the moment and my tuner doesn't provide live data. And yes fuel pressure is good (tested it two days ago when i noticed the hesitation at take off the first time.) and i only get diesel by the interstate where i know it's good.

Truck info...
2004.5 3500 CTD
LWB RWD
Auto trans.
Economy tune
5"turbo back exhaust.
 

·
Registered
Joined
·
62 Posts
Since it's most likely an injector dumping fuel uncommanded into the cyl, you gotta cap the high pressure inj line to see which inj is doing it. Well another less safe option is to idle the engine and use a heat gun to see which cyl heat is different that the rest, but I don't think that would be the way I'd go. I'd get a cap.
 

·
Registered
Joined
·
491 Posts
yep ^, same as the other thread that's been active, guy had the same thing, need the rail cap which is like a $20 tool or find a used injector line and crimp it shut (not as safe but have seen people do it long as you don't stand near the engine bay yourself.)

Now that you've pulled them you might have more trouble depending on the state of the tubes. Those 3 may not seal again and you'll need 3 new tubes. Won't know until you reinstall though.

So now you either reinstall those 3 and do the cap test or pull all 6 and ship them off to be tested and be prepared to buy 6 tubes instead of 3 + replace whatever injectors are bad.
 

·
Registered
Joined
·
4,882 Posts
What is the manifold soaked in, diesel? You can either send your injectors out to be tested, or if your snap on tablet has the capabilities of turning off the injectors one by one, you can try that and see if the smoke clears up when an injector is shut off. You can still have bad injectors even if they ohm out just fine.
 

·
Registered
Joined
·
4 Posts
I just had a similar issue and I bought the 20$ test cap and went down the line (starting with #1 since it's the easiest) and sure enough, when I capped #6 the knock and smoke went away. I bought this truck non-running, so I don't know how long it was leaking, but it was bad enough to cause carbon buildup in the cylinder increasing the compression to 600 PSI (all other cylinders @ 460-480). I ended up ordering all new injectors from injectors direct, but that was more due to the other unknowns on this truck and wanting to start fresh. When I talked to their tech support about the cost of testing the injectors, it just didn't make any sense for me to go that route, it was 50$ to test each one, and I think 100$ to clean them if they were good, which ended up being just a little more than a reconditioned one. To save as much $ as possible, I would buy the cap, identify the bad injector, replace it with a reconditioned one from a reputable source and reuse the rail lines and the injector tubes. The injector tubes are supposed to be one time use, but it sounds like you already have 3 injectors out, and I have heard of lots of guys reusing them multiple times (usually increasing the TQ on the retaining nut slightly to ensure a good seal). Good luck, and let us know what route you end up taking and how it works out.
 

·
Registered
Joined
·
1,282 Posts
Do the key on three times code tests, reads out in odometer window. Displays DONE when last code is displayed.
Write down and post.

Pull an oil sample and send in to oil test lab for analysis diesel contamination in the oil.

Run a compression test and post results.

Post up all numbers on each injector.

Most likely leaking injector nozzle pintle/s, leak raw liquid diesel into cylinder 360d of rotation. One blockoff fitting is not enough to find multiple leakers.
Soak the injector nozzle ends in MEK or acetone overnight if you can't locate the leaker. Try injectors.

Do you smell raw diesel while cranking motor, injectors in?

You've stepped into the modern world of HPCR diesels, expensive. Be ready for parts price shock.
Cheap parts in these kill engines.

Once you have white smoke problem solved, these MUST had HD commercial fuel water separator and dirt filters. OEM factory tiny insufficient ineffective filter is an engine killing POS. Lubricity fuel additive 100% of the time.

What engine mods?
 

·
Registered
Joined
·
14 Posts
Discussion Starter #7
Since it's most likely an injector dumping fuel uncommanded into the cyl, you gotta cap the high pressure inj line to see which inj is doing it. Well another less safe option is to idle the engine and use a heat gun to see which cyl heat is different that the rest, but I don't think that would be the way I'd go. I'd get a cap.
I actually just ordered the cap, Should be here tomorrow!
 

·
Registered
Joined
·
14 Posts
Discussion Starter #8
What is the manifold soaked in, diesel? You can either send your injectors out to be tested, or if your snap on tablet has the capabilities of turning off the injectors one by one, you can try that and see if the smoke clears up when an injector is shut off. You can still have bad injectors even if they ohm out just fine.
Yes, diesel. And I know it can on gasoline engines, Haven't done much of anything diesel before. I will try it when I get it back but I hopefully will have this figured out by then.
 

·
Registered
Joined
·
14 Posts
Discussion Starter #9
Do the key on three times code tests, reads out in odometer window. Displays DONE when last code is displayed.
Write down and post.

Pull an oil sample and send in to oil test lab for analysis diesel contamination in the oil.

Run a compression test and post results.

Post up all numbers on each injector.

Most likely leaking injector nozzle pintle/s, leak raw liquid diesel into cylinder 360d of rotation. One blockoff fitting is not enough to find multiple leakers.
Soak the injector nozzle ends in MEK or acetone overnight if you can't locate the leaker. Try injectors.

Do you smell raw diesel while cranking motor, injectors in?

You've stepped into the modern world of HPCR diesels, expensive. Be ready for parts price shock.
Cheap parts in these kill engines.

Once you have white smoke problem solved, these MUST had HD commercial fuel water separator and dirt filters. OEM factory tiny insufficient ineffective filter is an engine killing POS. Lubricity fuel additive 100% of the time.

What engine mods?
I don't smell raw diesel no. I get parts relatively cheap thanks to my commercial account at Diesel Performance Parts in Nashville. and as far as engine mods Im not sure besides some cheapo CAI the guy before me put on. I am not a huge "Modder". Although I have owned a duramax before and do believe a good tuner can be a great benefit which is why I got one. Other than that not really sure.
 

·
Registered
Joined
·
14 Posts
Discussion Starter #10
I just had a similar issue and I bought the 20$ test cap and went down the line (starting with #1 since it's the easiest) and sure enough, when I capped #6 the knock and smoke went away. I bought this truck non-running, so I don't know how long it was leaking, but it was bad enough to cause carbon buildup in the cylinder increasing the compression to 600 PSI (all other cylinders @ 460-480). I ended up ordering all new injectors from injectors direct, but that was more due to the other unknowns on this truck and wanting to start fresh. When I talked to their tech support about the cost of testing the injectors, it just didn't make any sense for me to go that route, it was 50$ to test each one, and I think 100$ to clean them if they were good, which ended up being just a little more than a reconditioned one. To save as much $ as possible, I would buy the cap, identify the bad injector, replace it with a reconditioned one from a reputable source and reuse the rail lines and the injector tubes. The injector tubes are supposed to be one time use, but it sounds like you already have 3 injectors out, and I have heard of lots of guys reusing them multiple times (usually increasing the TQ on the retaining nut slightly to ensure a good seal). Good luck, and let us know what route you end up taking and how it works out.
I have a feeling that it is my #6, The line went out while hauling a car hauler with 2 cars on it. I didn't know it until I turned on my air and diesel fumes came through the vents stinking up the whole cab. I am thinking that may have had something to do with this issue considering I did not know how long it was blown for and drove like that up and down hills in Middle TN.
 

·
Registered
Joined
·
4,882 Posts
That's really weird. I wonder how diesel got over to that side of the engine onto the manifold. Was there any fuel on the bottom of the hood?

Sent from my SM-G930V using Tapatalk
 

·
Registered
Joined
·
14 Posts
Discussion Starter #12
That's really weird. I wonder how diesel got over to that side of the engine onto the manifold. Was there any fuel on the bottom of the hood?

Sent from my SM-G930V using Tapatalk
None what so ever. I will take a pic tomorrow and post it. should still be there since diesel doesn't evaporate like gas. Im just thankful my buddy I met at the VA owns a tow company here. towed me for 50 bucks.
 

·
TECH SPECIALIST
Joined
·
11,029 Posts

·
Registered
Joined
·
14 Posts
Discussion Starter #14
Just an update. I got the rail plug in and just as I thought, #6 is the culprit. Capped the rail on #6 port and smoking stopped. DPPI is sending a driver with my injector to me now as I am typing this. Will have the truck running by this afternoon!
 

·
Registered
Joined
·
1,282 Posts
Run a compression test on #6.

Watch for signs of the other 5 going didi mau like a hawk. White smoke is the kiss of death in these.
 

·
Registered
Joined
·
14 Posts
Discussion Starter #16
Oh I will! Business has been slow so i couldn't afford all 6 at once but over the next several weeks I'll be replacing the remaining 5 as I can afford it. I will say I have never done a compression on a diesel before. I'll have to see if my snap-on dealer has the test kit. I'm sure there are multiple kits considering each diesel is unique in a way especially a ctd since I'm assuming you have to test compression through the injector hole.
 
1 - 16 of 16 Posts
Top