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Discussion Starter · #1 ·
Is this alright? It seems like it smokes more than it should. I don't know where the fuel screw is set, but i have not touched it since I got it. I have yet to get a boost gauge, but I think it is time. I am going to check all of the boost elbows and make sure there isn't a leak somewhere. It smokes like CRAZY if my converter stays locked and rpms drop and i give it any fuel at like 25-30. I started keeping the converter unlocked unless i was cruising at decent speed.

http://www.youtube.com/watch?v=PyUqgcH7m0Y
 

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Yes. my cpl 858 smokes just like that if I get into the pedal at low RPM's. I bet I could back off the smoke screw, as it seems to be giving it alot of fuel before the boost catches up. Once my turbo is spooled, the smoke completely clears up. Then again, it's fun to be able to control the smoke at will and leave a big cloud if I'm in a hurry.
 

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I must have spent too much time around old diesel farm and
construction equipment....I don't consider that bad smoke at all.
 

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Discussion Starter · #5 ·
it's over fueling and it does that because of the screwed in to much or your turbo has a lot of lag.

CrewCab59
hmm, it's the stock turbo with stock exhaust housing, so it probably does have a lot of lag. I think I will try and back the fuel screw off a hair and see what happens. Would advancing the timing help at all possibly?
 

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Advancing the timing will not help much if at all. If you do not have an EGT gage then I would not advance the timing either, you can get it pretty hot and not know it. Like CrewCab59 said the pump is over fueling before the turbo spools up.
Here is a useful boost leak tool I have made;
Make your self a pair of plugs for your intake tubes by using a couple of PVC caps from a box store. Put one coupler on the intake pipe where it attaches to the intake plenum using the rubber coupler. The other cap drill and tap for an air fitting and gage, install it where the intake pipe would connect to the turbo outlet. Now pressurize to 15-20 PSI and then you can listen for leaks without the engine running. Due to poor hearing I spray soapy water around every joint and look for bubbles. Let it sit for a little while and see if it looses pressure.
 

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Discussion Starter · #7 ·
Advancing the timing will not help much if at all. If you do not have an EGT gage then I would not advance the timing either, you can get it pretty hot and not know it. Like CrewCab59 said the pump is over fueling before the turbo spools up.
Here is a useful boost leak tool I have made;
Make your self a pair of plugs for your intake tubes by using a couple of PVC caps from a box store. Put one coupler on the intake pipe where it attaches to the intake plenum using the rubber coupler. The other cap drill and tap for an air fitting and gage, install it where the intake pipe would connect to the turbo outlet. Now pressurize to 15-20 PSI and then you can listen for leaks without the engine running. Due to poor hearing I spray soapy water around every joint and look for bubbles. Let it sit for a little while and see if it looses pressure.
Sounds like a plan. An EGT gauge will be ordered shortly, with the boost gauge actually.
 

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Discussion Starter · #8 ·
I must have spent too much time around old diesel farm and
construction equipment....I don't consider that bad smoke at all.
It could be worse, But I don't want my truck to look like a piece of old diesel farm or construction equipment :grinpimp:

Is there anything else that could cause this type of smoke? something that I'd need to address, IP or anything? That's really all i'm concerned about is that my engine is in good shape.
 

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The other thing to check is bad air flow ,if it's choking for air than it will always smoke as long a your fuel screw isn't turn in.



CrewCab59
 

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A plugged JWAC could give the same symptoms. They have a tendency to collect dust which can cause rust that restricts air flow. As I recall Carl had a chunk of air filter stuck in his. It might be a good idea for everyone to check theirs (provided you have one) before installing the engine.
 

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Discussion Starter · #11 ·
The other thing to check is bad air flow ,if it's choking for air than it will always smoke as long a your fuel screw isn't turn in.



CrewCab59

I have a 6x9 AEM filter on it. I am going to pull it and see what happens then. I don't think that it would be causing the smoke.

I did pull off the boost tube and stuck my finger down into the JWAC, I did not feel any debris in there.
 

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You won't always find it has plugged by feeling for debris. Here is the bottom of one that I have that has apparently plugged. Notice the holes that someone drilled through the core to allow additional air to flow through the rusted fins.
 

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Discussion Starter · #13 ·
You won't always find it has plugged by feeling for debris. Here is the bottom of one that I have that has apparently plugged. Notice the holes that someone drilled through the core to allow additional air to flow through the rusted fins.
AH! I will take it off and see what it looks like then. Anything special I need to know about taking it off? If it is like that, are there any options other than finding another one? Maybe an aftermarket cooler that I could put in there?
 

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guess I need some sleep....it took me almost half of the video to figure out that the screen was turned 90deg.....:idea: :eek: LOL
 

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Don't feel bad... For the life of me, I couldn't figure out what part of the vehicle I was looking at. I thought there was a stack on a durango!
 

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LOL!! Damn...
 

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Discussion Starter · #17 ·
Don't feel bad... For the life of me, I couldn't figure out what part of the vehicle I was looking at. I thought there was a stack on a durango!
HAHA sorry guys, i only had my camera phone to play with, hence the crappy quallity too.

I will be ripping apart the JWAC either tonight or tomorrow, unless i can find another place i'd be leaking boost or blocking airflow.
 

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Discussion Starter · #18 ·
well, I finally got the JWAC off tonight. That thing is pristene! no rust at all, flows evenly, so that's not causing any smoke. Could it just be turbo lag? It does seem to go away after rpms come up..
 
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