Engine/Transmission (1994 - 1998) I got SMOKE. Why?

[Reddog1]

I made several mods, including fuel plate and 370 injectors. I have adjusted the AFC, to minimize smoke. I did a good job, if I say so myself. Ran great, had smoke, but only if I really leaned on it. Great, I stopped adjusting.



Here I am about 1500 miles later, no further mods or adjustments. Now for reasons I cannot identify, I am progressively getting more smoke. I have run fuel from no less than three different sources.



I am going back to the drawing board today with adjustments.



Anyone with any ideas?





Wayne

 

[Deezul1]

Maybe dirty air cleaner, around here it smokes more when humidity is high so a rainy day or high humidity will contribute to smoke.

 

[Reddog1]

Deezul 1, thanks for the input.



Less than 2000 miles on Fleetguard BHAF. It appears cleaner than a whisle.



Smokes at in Sacramento valley and in San Francisco. Outside temp from 56 to 92 degrees. More obvious at night than in day.



Don't know humidity, but substantially different between Sacramento and San Francisco.





Wayne

 

[Deezul1]

The air cleaner sounds good. Night will always look worse unless there are no headlights behind you then it looks pretty good back there. How is your boost? is it dropping any? That will give a rich mixture condition and it doesnt take much. When I put my 11 plate in the 370s were already in and boy did it smoke. Adding the BHAF cut the smoke in half so it doesnt take a lot to increase it.

 

[T. Baker]

How about you got used to the power and now you are flooring it alot and running it up to the govenor more!? Seriously though I do get alot more smoke when I am over about 2400 rpm and I have noticed that I don't like to let obnoxious expensive SUVs pass me indiscriminantly and for no other reason than they think my truck looks slow. So I have gotten used to pushing a little harder at the upper end of the rpm range and that makes a little more smoke. Is your boost still the same? Could you have an intercooler or piping leak?

 

[1dslram]

Is it possible that as you are getting used to your new power you are using more and more of it? More power = MORE SMOKE.



Bruce

 

[Reddog1]

I just got back from tweaking and testing. I may need all new AFC components, just about have these worn out tweaking.



Thanks for the responses.





Deezul 1 – what headlights? They disappear so fast, I thought they were turning off their lights.





T. Baker – well, yea. I admit, I appreciate the smoke when followed by a tailgater. A little more smoke is not my problem, a lots more is. My boost is still the same. Even at that, I bought the parts to pressure check the intercooler and piping for leaks.





1dslram - Is it possible that as I am getting used to my new power I am using more and more of it? ABSOLUTELY. Oo. I will accept more power = MORE SMOKE. I am pushing 60 years old, and if my granny were still alive, she would make it smoke going to the store. I mean the exhaust also.





Since my last post, I checked the following:



Fuel plate – has not moved.



AFC Foot and shafts – they move freely, with no binding.



AFC Housing – had not moved, about ¾ forward.



AFC pre-load adjustment screw – had not moved.



AFC Star Wheel – had not moved.





I found no problems with any of these parts or adjustments. Then I made the following adjustments, one at a time, testing each, with no decrease in smoke.



AFC Diaphragm cupped washer – removed and replaced with a flat washer.



AFC Housing – moved to the back (firewall) and the front.



AFC pre-load adjustment screw – adjusted to zero pre-load and to three turns pre-load.





I have to be missing something.





Thanks,



Wayne

 

[dvieira]

hmmmm???

since i installed the Fleetguard 19037 BHAF & the Outerwears

prefilter, i also am getting more smoke, and lower boost at around 23#, and that's towing up Hwy 80 to Reno 2 wks ago,

with my 5th wheel, i've read on this forum last week that somebody mentioned that maybe the prefilter was restricting

air into the filter, so am taking the prefilter off and see if

that will make a difference.



dave

 

[JSmith]

Guys with California trucks check the boost fitting on the back of the afc for restrictions from soot by way of the cross over (EGR). Mine was plugged and I had very little power. Its worth a check.

 

[HEMI®Dart]

Reddog1



Have you adjusted the no load fuel adjustment screw? This is the allen setscrew w/ a 10mm locknut on the back of the AFC. You could try to back this out a little. Turning it in gives more preboost/low end fuel. Turning it out reduces it. It just moves the AFC dog back or forward a little.

 

[Missouri Mule]

Reddog1,



I take it your getting black smoke, if not what color?



Black smoke = to much fuel for the amount of air (oxygen) in cylinder.

Dumping more fuel into cylinders than needs to be, air leak in intake system (not enough air gettting into cylinders).

 

[carson6]

j smith....

I checked my egr tube and cat and they are hanging on the wall still!

 

[Reddog1]

Dave – I installed the Fleetguard BHAF only, no Outerwear’s. On real hard acceleration, I get 35-lbs. boost. Just an afterthought, if I don’t have Outerwear’s on my BHAF, does that mean I am running around in my undies?





Jsmith – I have a federal Ram, so I get to skip the EGR issues.





HEMI®Dart – I have adjusted the no load fuel adjustment screw. And I agree that turning it in gives more preboost/low end fuel (with more smoke).





Missouri Mule – The smoke was black. Initial startup and under acceleration.





carson6 – My EGR was missing from the factory. They forgot to remove the Cat. I will soon do that for them.





I think I now have the smoke as controlled as I will be able to get it. I have been communicating with several people on the AFC and it’s adjustments. I will probably make a long post on the AFC adjustments. Overall, it appears there is not a clear understanding of the AFC adjustments.





I finally have the smoke down to a short puff at startup. Then if outside temp is cool, the black puff will be followed by a bit gray. On starting, I press accelerator about ¼ down. On acceleration, smoke not noticeable from mirrors. Moderate acceleration, a gray haze. Hard acceleration, moderate gray-black smoke you can see through.





After setting my Fuel Plate to stock position, I adjusted my AFC.



My AFC settings (and sequence) are as follows; AFC Housing slid ¾ forward, removed AFC End Cap to insure no binding of AFC Foot, stock AFC Spring, no modification of AFC Diaphragm cup washer, re-install AFC End Cap, back-out the AFC no load fuel adjustment screw, turn-in with fingers to just make contact with AFC Diaphragm Shaft.







Please explain the gray smoke.







Wayne

 

[Deezul1]

Gray smoke usually is from unburnt fuel when motor is to cold for good combustion. Try cycling your grid heaters twice and see if it makes any difference

 

[Reddog1]

Deezul 1



Thanks I will give that a try.





Wayne

 

[T. Baker]

I have notieced that light black smoke can look grey especially when it is darker outside and you are seing it by the headlights behind you.

 

[krs]

Reddog1,



Have you given thought to the possibility that all of the new activity (higher fueling, more accelerating, tuning/revving, etc. ) may have caused things to loosen inside your exhaust system and plug or partially plug the flow? By any chance does your exhaust seem quieter if you stand at the tailpipe than it used to, before mods? What goes in (air, fuel) gots to go out with equal ease.

 

[Reddog1]

T. Baker - I agree. I am referring to the gray smoke in daylight. In all probability, it is black, just less of it.





kshine - I doubt that anything has loosened in the exhaust system that could have this effect. Due to how quick the EGT's go up, I think the Cat will have to go.





As I stated in my previous post, I think I have done about all I can do with the smoke. Now I have to address the EGT.



I spoke to Piers last week, and he said some of the symptoms suggest an intake leak, and possibly Cat restriction.



My maximum boost is about 35-lbs. This is under hard acceleration. With a 2600 lb slide-in camper, cruising on flat ground, at 70 MPH, I have about 16-lbs boost and 1300 EGT.



If I accelerate quickly, boost jumps to 35-lbs , EGT's jump almost as quick to 1500 degrees and the truck scats Oo. .



What do you guys’ experience under similar circumstances, with a slide-in, 5er or tongue dragger?







Wayne

 

[M Barnett]

I don't know which fuel plate your running. My truck smokes pretty bad when I open her up, but no smoke under 10 lbs of boost with normal driving. My pyro would climb about as fast as the speedometer. I got a 16 housing from Piers and it helped the egt's a lot without hurting the spoolup time. It will still hit 1500*, but takes much longer to get there and I swear it helped the smoke. Now I can see through the cloud. With the 16 housing, the boost is 35.

Michael

 

[Reddog1]

M Barnett - Thanks for the input. I am running the #11 plate with 370 injectors.



My next mod will probably be a bigger housing. Piers suggested I block off the wastegate, to determine if I needed a wastegated housing or non-wastgated. I am using his wastegate elbow.



Before blocking I had 35-lbs boost, after blocking, I had 37-lbs boost. This suggested to Piers that I might have an intake leak. He expected more boost after blocking the wastegate.



Because I am complaining about turbo lag, he suggested I should not go to the 40.



I have an auto transmission. Depending on the TC, it appears that the auto may have more turbo lag than the stick shift.





Wayne