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Excessive Black Smoke on Acceleration


StewB

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Well, it appears I have a new issue with my truck. Under acceleration I get a fairly thick cloud of black smoke along with sluggish acceleration. The harder I mash the pedal the worse it gets. It rarely ever smoked before unless I turned the Minimaxx up and romped on it. Even then it wasn't near as bad as it is now. Some background:I've just moved from Alaska to Utah. I drove roughly 3500 miles with a gross weight of 22,000 pounds. Minimaxx was set on the Tow setting (+60hp). At the beginning of the trip the temps at 65mph on relatively flat ground were as follows:Ambient 60*Coolant 195-200Tranny 170-180Egt 900-1000When I got to Washington state the temps were sitting atAmbient 95Coolant 210+Tranny 190-200Egt 1000-1050During hill climbs, of which there were 100's, my egt (pre-turbo) would climb well into the 1300's and occasionally briefly spike over 1400. I was a little concerned about the temp increases, particularly the coolant, but attributed them to the rise in ambient temperature. We picked up a car in Seattle and my wife told me at our first rest stop that I was blowing more black smoke than normal. She's followed me a lot before so I trust her opinion on this. I attributed that to being about 5,000 pounds heavier than ever before and having to lay into the throttle more; however now I'm not sure I was right. Now that we are in Utah and empty again it is still blowing excessive black smoke, even under light acceleration. The turbo also seems to take too long to spool up. It's well into the 90's here and I've never driven this truck in temps warmer than 80* mostly under 60, so I don't know what to expect in a hot climate. The truck is very sluggish for 2-3 seconds from a stop but seems ok at cruise. I haven't even run a full tank through yet so I don't know my current mpg. I got 9.8 mpg on the trip. I've read some possible problems could be bad/dirty injectors, dirty air cleaner or MAF, or problems with the turbo. Worst case was a melted or deformed piston. Any opinions on where I should start? I eliminated the air cleaner and MAF.I can provide more info but don't know what else would be helpful. Thanks,Stew

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Additional info. Now that I'm in Utah my boost psi at idle has gone to 0 where it used to be 1-3. Last night I revved it in Neutral to 2000 rpm for a few seconds with no increase to boost psi. In gear it eventually responds as described in the previous post.

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Yea... Time to pressurize the system and use soap solution and spray down all the air system looking for leaks. It could be really simple as a boot with a small hole, intake bolt blown out, intake gasket blown, etc. Typically easy fixes but would explain the higher temps and more black smoke.

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Thanks all for the suggestions. I hadn't thought of a leak in the intake system, but then that's why we come to forums like this. Will poke around and see what I find. Thanks, Stew

Update???? What did you find out.......if anything????:smart::thumbup2:
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Sorry about the slow leak on the update. Nothing to tell yet. I looked around under the hood for a half-hour and didn't see anything. I'm taking it to a place called Wild Diesel in West Haven, Utah, on Friday. I'm in the middle of a move and most of my tools aren't with me, so I just don't have the time or resources to do any more right now. More to follow...Stew

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I agree with boost leak, thou the EGT's you let the truck climb to while towing have me worried as well. On a timing modified 06 you want to try to limit to 1250° continuous and 1300° momentary. The 04.5-07 pistons are the easiest to melt. You should have 0 psi at idle, but with the digital readout you may bump 1, but that should be it unless you have a REALLY plugged air filter (still a possibility). The HE351CW in your 06 should make 2 psi at 2000 rpms, 4 psi at 2500 rpms and about 7 psi at 3000 rpms. That's with a analog gauge, the minimax should show slightly more.Don't worry about the coolant temp. The stock thermostat goes full open at 207°, with a max allowed temp of 225°. I generally run 215-216° pulling grades in the summer.

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I agree with boost leak, thou the EGT's you let the truck climb to while towing have me worried as well. On a timing modified 06 you want to try to limit to 1250° continuous and 1300° momentary. The 04.5-07 pistons are the easiest to melt. You should have 0 psi at idle, but with the digital readout you may bump 1, but that should be it unless you have a REALLY plugged air filter (still a possibility). The HE351CW in your 06 should make 2 psi at 2000 rpms, 4 psi at 2500 rpms and about 7 psi at 3000 rpms. That's with a analog gauge, the minimax should show slightly more. Don't worry about the coolant temp. The stock thermostat goes full open at 207°, with a max allowed temp of 225°. I generally run 215-216° pulling grades in the summer.

It's like reading a flight manual. Impressed. :thumb1:
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Boy do I feel stupid. It turns out it was a clogged air filter. I ASSumed there was no way it was the filter because I cleaned it the day before I left Alaska and only put 3500 miles on it. Other than a few bugs, it also didn't appear clogged when I was looking around under the hood.Ken Jones at Wild Diesel in West Haven, Utah, did an injector test and verified they were within spec. They also checked rail pressure and it was good. Turbo and everything downstream checked out as well. When he took it for a test drive he saw the same symptoms I did, pulled over on the freeway and took the filter off, which fixed the problem. Ken really did me right. He didn't charge me a dime for his diagnostic time. He said the Airaid filter was probably no good any more and recommended I replace it. He offered to order one for me; however I never liked the Airaid Quickfit system that was on the truck when I bought it, so I asked him what he recommended for cold air intakes. I ended up getting an S&B air intake system based on his recommendation. He had it in stock so I put it on tonight and drove about 60 miles without a problem. Anyway, lesson learned was never assume anything. The upside is I found a good shop should I need one again. Thanks again for all the inputs and suggestions. Stew

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@AH64ID, thanks for the boost and temp specs. I feel better about my running temps and boost pressure now. Looks like I have a learning curve for pulling with a diesel in a hotter climate. I didn't have these issues in Alaska. ? With my airflow problem fixed maybe the egt's will be easier to manage.

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Boy do I feel stupid. It turns out it was a clogged air filter. I ASSumed there was no way it was the filter because I cleaned it the day before I left Alaska and only put 3500 miles on it. Other than a few bugs, it also didn't appear clogged when I was looking around under the hood.

Ken Jones at Wild Diesel in West Haven, Utah, did an injector test and verified they were within spec. They also checked rail pressure and it was good. Turbo and everything downstream checked out as well. When he took it for a test drive he saw the same symptoms I did, pulled over on the freeway and took the filter off, which fixed the problem.

Ken really did me right. He didn't charge me a dime for his diagnostic time. He said the Airaid filter was probably no good any more and recommended I replace it. He offered to order one for me; however I never liked the Airaid Quickfit system that was on the truck when I bought it, so I asked him what he recommended for cold air intakes. I ended up getting an S&B air intake system based on his recommendation. He had it in stock so I put it on tonight and drove about 60 miles without a problem.

Anyway, lesson learned was never assume anything. The upside is I found a good shop should I need one again.

Thanks again for all the inputs and suggestions.

Stew

The problem is that all washable media filter tend to either break down over period of washing cycles and then filtering ability is reduced. Then the other side is the problem you had where its plugged up and can't be properly cleaned any longer. Other problems is people tend to improperly wash the filter and now deposit dirt on the intake side and allow engine now to inhale the dirt.

One of the few reason I tend to fall back to a paper element where its its service life is over then toss out the dirty element and replace with a new filter.

I can understand the big thing for high flow filters and cold air intake for racing applications where the engine is ran WOT at high boost down a track. But for daily driving where you might use a short burst of boost but typically low boost there is no need for the fancy hi-flow filters.

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... But for daily driving where you might use a short burst of boost but typically low boost there is no need for the fancy hi-flow filters.

I have to agree but let's just say there are many victims of good marketing out there, including me. The fuel economy gains they claim are too tempting to pass up. ?
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The fuel economy gains they claim are too tempting to pass up. 

Stock is the best you can run below 450-500 rwhp, period. Mileage claims are bogus, think about it, when you are cruising your airflow is low. If your stock filter were hindering flow at 4-8 psi of boost while cruising do you think it could keep up with 32 psi of boost and WOT? If a filter is able to increase the flow that much at a low flow condition then it is either HUGE, much bigger than they are, or it has lower restriction and generally less filtering ability.
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