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General Information => Troubleshooting => Topic started by: ant_43 on January 10, 2010, 07:17:42 am
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I know it's a common problem with these old diesels, but my smokey startup persists and i'd really like to fix it finally! I've read through a lot of threads on this here, but thought it worth asking about my specific problem.
Engine spec: 1.9td aaz, K03 turbo, GTD/1.6TD Injection pump timed to 0.95mm, GTD injectors, newish glow plugs, newish battery, slightly upped the fuel (1/8 - 1/4 turn, which i think it needed for the 1.6 pump to suit the 1.9).
To try to eliminate the smokey startup i have replaced the glow plugs, battery, had the pump timed, and just recently had some rebuilt GTD injectors with new nozzles fitted. I was hoping that the GTD injectors would clear the smokey startup problem, but it actually smokes more now and i seem to have a bit of a miss on idle and low revs (which i've only noticed since installing the new GTD injectors)?
On cold starts i have a lot of white smelly smoke, and have to use the cold start knob or rev it, as it runs so rough and it will stall quite quickly. If i do use the cold start knob the smoke clears considerably and the engine idles smoother. I shouldn't need to use the cold start knob in the UK right?!
After it is warmed up and with the cold start knob pushed in, the engine seems to idle quite nicely, apart from with a little miss every now and then? The engine seems to perform well, and the new injectors did have an improvement with the performance, although i am only getting approx. 36mpg. The engine starts fine from warm.
This morning i started the engine up and looked it over and noticed a small amount of the same white smoke appearing from the back of the head - by the exhaust manifold. I could not see exactly where this was coming from. It seemed to disappear once the engine had warmed up. There is no sign of oil in water / sludgeyness in the expansion tank, and the oil looks fine which would suggest headgasket is ok?
I am running out of parts to change to fix this now, please help!
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All depends on the temperature there really. How cold is it out? As the age of the vehicle goes up then things do wear and they like to start with more advance..
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and have to use the cold start knob or rev it, as it runs so rough and it will stall quite quickly. If i do use the cold start knob the smoke clears considerably and the engine idles smoother. I shouldn't need to use the cold start knob in the UK right?!
Your car is telling you that you need to use the cold start knob.
Do you have an afterglow on the glowplugs? AAZs normally have one.
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What about bumping the timing up 0.05mm? to 1.00mm or even 1.05mm if it likes it.
It helped my old smokey 1.6 tremendously lol. I upped the timing to 1.02 (n/a motor) from what i believe was set at or around 0.90-0.95.. Smoke went away completely.
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I too think it needs more advanced timing, seeing how the cold start knob help it anyways.
Also IIRC GTD injectors have a higher pop pressure which will retard the timing even more, hence why it made more smoke. ;)
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Thanks for the replies. That makes sense to me to perhaps bump the timing up a bit to suit the injectors. I spoke to the garage that fitted the injectors, (next door to my work!) and they have suggested that also. Unfortunately they don't have a dial gauge, for that i have to use the other garage that rebuilt and tested the injectors ::) :D
For now i've reduced the fueling a little, which has reduced the smoke slightly.
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For now i've reduced the fueling a little, which has reduced the smoke slightly.
You could reduce the fueling completely, but if the pump is injecting fuel to early (retarded timing) it will always smoke. The fuel is being injected before it has time to burn properly, and then getting shot out the tail pipe :P.
I'll put money on advancing the timing :)
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For now i've reduced the fueling a little, which has reduced the smoke slightly.
You could reduce the fueling completely, but if the pump is injecting fuel to early (retarded timing) it will always smoke. The fuel is being injected before it has time to burn properly, and then getting shot out the tail pipe :P.
I'll put money on advancing the timing :)
I understand. I hope doing the timing is going to sort this out finally! It's booked in for friday so we shall see!.... :)
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Well if it is already timed to 0.95mm.. they may time it close to that for when they do it. Tell them to time it to 1.05, a lot of stock td's like this with normal nozzles. With your GTD nozzles and higher popping pressure they will probably like it being timed that advanced.
Ask them what they are going to time it too. anything over 1.00mm is probably ok. Higher then 1.05mm may be too high.
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You could reduce the fueling completely, but if the pump is injecting fuel to early (retarded timing) it will always smoke. The fuel is being injected before it has time to burn properly, and then getting shot out the tail pipe :P.
I'll put money on advancing the timing :)
8V you lost me on that one haha ;D, earlier injection is called advanced timing and the fuel can't be injected "before it has time to burn properly" :P. It can only get shot out the tailpipe unburnt when the timing is late (retarded) :P
Perhaps I read it wrong? ::)
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You could reduce the fueling completely, but if the pump is injecting fuel to LATE (retarded timing) it will always smoke. The fuel is being injected, doesn't time to burn properly and is getting shot out the tail pipe :P.
I'll put money on advancing the timing :)
One word wrong and your on my back :P I still had the right idea goin on eh lol
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You could reduce the fueling completely, but if the pump is injecting fuel to LATE (retarded timing) it will always smoke. The fuel is being injected, doesn't time to burn properly and is getting shot out the tail pipe :P.
I'll put money on advancing the timing :)
One word wrong and your on my back :P I still had the right idea goin on eh lol
haha that's better ;D
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Right, i've taken it to the garage and now have a big question...
I stayed at the garage while they did the work and asked lots of questions, plus that way i don't get overcharged hehe.
We advanced the timing, not using a gauge though, by ear. It now starts a lot easier, runs better when cold, and minimal white smoke on startup. Although there is still some white smoke, and a little miss / popping remains. I understand this could be valve stem seals? - Requiring taking the head off. >:(
Anyways, my big question. With the GTD pump fitted to my AAZ, the pump pulley is not in line with the rest, thus the cam belt has been running off the centre of the pulley and has been wearing away. :o This is obviously a major concern and something that requires attention asap.
Now the garage could not understand why i would want to use a 1.6 gtd pump and 1.6 td injectors on a 1.9 engine. I used the pump originally because it had less electrical gubbins on it and i have heard they are more tuneable, but now i wonder whether it was the right thing to do. ???
I still have the original AAZ pump. So now i have a decision to make for when i replace the cambelt.
1. Keep the gtd pump fitted, but use the pulley fitting from the aaz pump on the gtd pump. (The garage said this would be possible so as to bring the pulley back in line)
2. Put the original AAZ pump back on, and remove the unrequired electrical bits. It is a late AAZ pump, which has a vacuum mechanism for cold start advance. Also, it has a domed LDA, but no "smoke" screw. I assume i'd be able to use the GTD LDA on the AAZ pump top? If i use the AAZ pump would i be advised to go back to AAZ injectors?
The garage mentioned the GTD pump has an 8mm element, while the AAZ pump has a 9mm.
Clearly i need some advise from the knowledgeable people here! Which pump would YOU use - or do i use parts from both pumps to build a "super pump" ;)
(Sorry for the length of this post!)
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the pumps both have the same pump heads. 9mm. the AAZ pump has a higher lift cam plate tho.
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the pumps both have the same pump heads. 9mm. the AAZ pump has a higher lift cam plate tho.
Ah. The mechanic checked the pump numbers in a book which told him that the elements (is this the same as the head) were different sizes, 8mm and 9mm?
Should i put the aaz cam plate on the gtd pump?
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Can anyone provide some more input on my little dilemma please?
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the pumps both have the same pump heads. 9mm. the AAZ pump has a higher lift cam plate tho.
Ah. The mechanic checked the pump numbers in a book which told him that the elements (is this the same as the head) were different sizes, 8mm and 9mm?
Should i put the aaz cam plate on the gtd pump?
the GTD pump should have a 9mm pump head. end of story.
yea, the pump head is the same as the element. but i sure as hell wouldnt call it an element. its a plunger.
the AAZ pump should be 9mm also if its a turbo pump. unless its an eco-1.9
not many people use the AAZ pump for performance build ups. the 1.6 pump is way closer to what you want in stock form. and much easier to modify from my experience.
i wouldnt just go swapping over parts from one pump to the other without knowing exactly what the outcome will be. you might wanna do some research before you tear into them and mess both of them up.
post up the numbers off the sides of the pumps, we can tell you more about them. we know for sure what numbers mean what.
and have you messed with your timing yet? all your symptoms point to retarded timing. setting the timing is alot easier than building a new pump, because you still have to time the new pump right also. timing is SUPER IMPORTANT!!! do you even know if its timed right? thats the first thing i would do before i did anything to the car. timing is easy to set, and it doesnt take much time. rotate the pump towards the engine about one pencil line. with the injector lines loose of course. you never want to attempt to adjust the pump while the injection lines are on it.
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Sorry the mechanic is an old guy (70s) so when he says element it may be an old term for that part. I'll try to get the different pump numbers and post them up here to clarify the size of the HEAD!
Please read my post before where i stated that we have adjusted the timing now, and it runs a lot better. My dilemma now is that i need to replace the cambelt, and wanted to know what would be the best pump / combo to use when this work gets done. As i mentioned, the mechanic has put some doubt into my mind as to why i have a 1.6 pump on a 1.9 engine.
I will not be swapping over bits of pumps myself, i would be likely to mess it up, hence why i use a mechanic to help out!
I have done a bit of research but would like to know peoples opinions and ideas of the best pump / or combination of parts for my engine in this particular situation.
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Ok, i have the pump number for the GTD pump which is currently fitted to the engine:
0 460 494 267
???
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most people use the TD pump because its so much easier to tune. and its alot better than the AAZ pump in stock form. the LDA pin actually does something in the TD pump. that pump you were talking about in the last post has a 9mm pump head in it. just stock. i would use that pump no matter what if the other one has a 8mm pump head in it.
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Ok, thanks for the reply. So the pump with number 0 460 494 267 has a 9mm pump head? That is what is fitted so think i'll use that one. Should i get the AAZ pump camplate fitted to this pump, get the alignment of the cambelt issue sorted and then call it a day?.... for the time being ;)
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you COULD throw the AAZ cam plate in there, but i dont know how its going to make your engine run. it needs quite a few other parts along with the cam plate, for it to run as it should.
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you COULD throw the AAZ cam plate in there, but i dont know how its going to make your engine run. it needs quite a few other parts along with the cam plate, for it to run as it should.
Ok, well i have both pumps so all parts from both pumps. What i need to know is which bits of each pump are going to be needed to create this hybrid pump, and still have a pump that works properly for my engine :) ???
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Any more input from you guys would be extremely helpful? :)
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The camplate is matched to the injectors - the AAZ camplate is designed for a 2-stage injector, so if you're going to use it you need to use AAZ injectors with it too. You may or may not need the pump head and delivery valves too, I'm not sure.
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The camplate is matched to the injectors - the AAZ camplate is designed for a 2-stage injector, so if you're going to use it you need to use AAZ injectors with it too. You may or may not need the pump head and delivery valves too, I'm not sure.
Ah really, grrrr! I've just had refurbed GTD injectors fitted! I've heard of people using GTD injectors / nozzles on a stock AAZ pump setup, so would i have significant problems with keeping the GTD injectors if i decided to try to use the AAZ camplate with the GTD pump?
I just need to get the cambelt sorted as a priority now.
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They'll WORK either way, IE your engine will run. But they really were designed to go together.