VWDiesel.net The IDI, TDI, and mTDI source.
Engine Specific Info and Questions => IDI Engine => Topic started by: colectb on July 28, 2009, 05:23:15 pm
-
I know its part of having a diesel, but what are some tips for reducing the black smoke when accelerating? Anything I can do to the car? (without delving into timing for the time being) I just don't like seeing that black stuff coming out, its one of the reasons why diesels are mistakenly seen as gross polluters.
-
Change the air filter??? Get more air for the fuel to burn more completely or turn the fuel down. You could search for how to make your 1.6/1.9 NA or TD a faster car in the FAQ and do the opposite of what is said to do with the fuel screw.
-
I have a 2.0 Audi 5 cyl TD, and maybe a custom intake with a cone filter on the end would draw in much more air? Or would it be too easy to become hydrolocked?
-
As long as you dont put the cone where water will be likely to be sucked up, hydro locking isn't likely.
Turn the fuel down, increase the exhaust, bigger intake, and less Lead Footing :) lol
-
I'm still kind of new to these engines, where exactly is the fuel screw and what direction does what? Is there any danger to running a little leaner like in gas engines?
-
You don't adjust richness or leaness. Your adjusting how much fuel is injected per where your foot on the pedal. Rich or Lean, or more correct Retarded or Advanced is adjusted by setting the timing of the pump with a dial indicator.
Search the FAQ there is wonders of info in there :)
-
turn up the boost too, that takes alot of smoke away too.
-
Hmmm, thats the best advice i've ever heard ;D
-
Have you ever had the injectors rebuilt if it's got a lot of miles on it? Worn injectors make a lot more smoke than good ones even though the car starts and runs good and have your timing checked and make sure your filters are good. If nothing else run a can of injector cleaner through it, it will definately make a difference if you've never done it.
-
Ok, thanks alot for all of the suggestions. For now i'm going to try:
1: A new air filter, or new intake system, I don't think the inlet to the airbox is big enough, i may go with direct plumbing to the turbo
2: Turn up the boost to probably around 12 psi where the k24 wastegate starts dumping.
3: Mess with the fuel and smoke screws, this is still a bit foggy to me, but i guess i will do some trial and error turning things down.
4: Fuel injector cleaner or diesel purge. I believe the injectors were replaced when the engine was rebuilt around ten thousand miles ago, but i don't think diesel purge will hurt.
5: Intercooler to make things a bit more efficient under the hood.
I just want the least smoke and best economy, while keeping or adding a bit of power, thanks alot for the suggestions, and I will keep everyone informed if I can significantly reduce the smoke.
-
For an easier fix than a new intake you could just turn the boost up.
Adjusting the "smoke screw" to pump less fuel in is like putting a block of wood under the go pedal.
-
Ok, I'm already running about .6 Bar so around 9 psi. I don't have a good boost gauge, just the stock one, but thats good enough for me. What would be a good pressure to set it to? Sorry for all of the questions, but coming from the NA gas porsche world to the turbo diesel VW/Audi world is quite a change
-
Press the pedal less hard...
Andrew, I don't wanna be the one to say it.. but you are lame ;) what kind of fun can you EVER have with anything being less hard lol
Pedal always %100 matted.. probably explains why i get 450kms a tank outta my 1.7 loool
-
Doesn't work, it always smokes while accelerating no matter the speed, i just cant see it in the mirror unless its matted down.
-
if you don't like Sootin' people out.. why drive a diesel? lol
every diesel i have ever seen smokes on acceleration i think. It's just how they roll Dawg. LOL
I mean do all those things u said.. as it will greatly increase every aspect of the car.. but i dont think u can get rid of smoke completely..
-
Alright, I'll still do them to see what they do, but yeah, I just don't like the smoke, if i could get rid of it i would, and it would help get rid of the misconception that most people have that diesels pollute way more.
-
Well smoke them out, soot there windshields.. then tell them your car is still cleaner then there Hybrid :)
-
I agree with 8v-of-fury let it smoke! ;D The more the better!
-
dyde, my audi smokes whenever i accelerate too. i think thats just the nature.
-
So thinking about that smoke screw then, that's for boost enrichment, is it not? I pull about .5 bar or 7 PSI while cruising around 65 mph, (105 KPH). Now I know someone said earlier that turning that thing down is like putting a wood block under the gas (err... diesel) pedal, but would the lack of boost enrichment, like that of the eco diesel, cause a noticeable increase in fuel economy?
-
would the lack of boost enrichment, like that of the eco diesel, cause a noticeable increase in fuel economy?
It depends on how you drive. If you never matt the pedal and hit the full load stop (I hope that's right, my brains broken at the moment) then it will make no difference. If your foot is always to the floor then removing the the LDA will limit the amount of fuel being injected while the turbo is producing boost. It's highly debated as to which will give you better fuel economy though
Freeing up your exhaust system will help reduce smoke because the turbo will be able to spool up faster.
Properly working injectors also make a big difference, especially in fuel economy.
An intercooler is definitely a good idea.
-
So will me boosting 7 psi constantly cause the LDA to be constantly injecting extra fuel?
-
So will me boosting 7 psi constantly cause the LDA to be constantly injecting extra fuel?
I don't think it will I'm not sure exactly when the LDA becomes affective but I think it's when your floored or nearly so. When you floor it the mechanism inside the IP hits a stop, but as boost rises the stop (which is hanging down from the LDA) is moved ahead with the mechanism still held against it by your foot, so more usable fuel is injected.
So if the adjustments are out of whack you might get too much fuel injected before you have enough boost to burn it all, so gray or black smoke.
I have studied an LDA but not in the car and I've never messed with one installed and tested each adjustment.
I've seen pics and explanations of what everything does on here, the search should turn up lots of usefull info. :)
-
My smoking issues (in normal driving) went away entirely with blocking the waste gate and removing the BOV.
black smoke is simply unburnt diesel. 1600cc can only naturally aspirate so much O2 in there so off the line or at the start of a new gear you're always going to have some excess if you're leaning into the pedal unless you have the worlds smallest turbo that spools up on idle.
-
If I'm not mistaken,the LDA affects the fueling at all times other than idle.
I have a hard time knowing exactly what the control mechanism is doing in there with the gov springs stretching and all.
Here's how I see it, with a NA IP there's a pin that stops the lever inside the pump, with a LDA IP there's the "movable finger" hanging down from the LDA that takes the place of the pin. So with the pedal not floored the lever is not against the pin on the NA or the "finger" on a TD.....I'm studying an LDA at the moment. To the naked eye it appears that the conical "boost pin" is evenly shaped all around yet off center, so turning it to the 'most fuel' position increases the fueling throughout the boost range when the pedal is floored, from pre-boost to full boost. I measured the LDA finger's travel at 1/32", as near as I could tell that remains constant however the conical pin is turned.
That being said, for the past two months I've been running a "modified" na pump with the stop pin removed and I haven't installed the LDA yet. The fuel limiting device is the "smoke screw" now rather than the stop pin also, the effects have been: the ability to make massive clouds of thick black smoke, or unscrew the "smoke screw" some and get a light haze of smoke.
I'm calling it a smoke screw simply because everyone will know what I'm talking about.....and I've forgotten the real name ::)
Feel free to correct me on this.
-
So will me boosting 7 psi constantly cause the LDA to be constantly injecting extra fuel?
Like rabbitman said.
Basically it gives you the potential to inject more fuel.