Hi VRS2, has your DPF problems remained 'cured'? I have had a similar problem for sometime and like you had a garage undertake the 'chemical clean' but still having issues. They replaced the EGR valve recently which, to be honest, has helped but not resolved the problem. I have also tried the propriety additives for the DPF, Turbo and Injectors but having seen what you have undertaken will revisit the issue again.
Just another VAG nut with anti-social coding complex
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Oil temp seems a little high considering all the other temps are between 20 and 23°. I would monitor/log the temps during a drive where you got everything fully up to temperature.
The DPF numbers are a bit puzzling. No ash at all at 155,000 miles? Yet quite a bit of soot. Check Differential Pressure Sensor readings in MVB 100. Post what you see there both with key on, engine off, and at idle.
You might also try clearing faults and then attempt to run a regen while driving. Hint: Adaptation channel 013; instructions should appear in a yellow info balloon.
Letting the car idle for many hours is generally a bad idea. Get a battery charger!
-Uwe-
I'm going to check that ash figure again Uwe, after the ECU has had some time to recalibrate what's happening. The DPF back pressure seems quite low, so presumably not much can be blocking the flow. I gather its the difference in the readings between two sensors, from which the state of the DPF is calculated. I think if the garage think the DPF is cleaned to such an extent they can enter zero ash, if that turns out to be wrong it wil reveal itself soon enough. I would expect to see higher numbers when i next check. The car is performing better than it had been since the five years Ive had it.
My next endeavour now is to do adaptation for gearbox clutches, but strangely I dont see any access codes for this for 02E DSG 6-speed box. I think I can do it from a cheap plugin. You'll know the answer on this one Uwe, I'm sure.
I have over time used various preparations on the shelves of good places for this kind of stuff and I pick judiciously but that doesn't mean I'm always right. For example I would say I expect Millers DPF cleaner to be better than leading brands, simply because they are a small specialist oil blender with a bit of a reputation for quality. I think the way this thing works is it gets to be like a mini furnace in a can and the ceramic comb inside is a means to catch and attract contaminents by providing a very large surface for the gasses to flow across or through. It would be interesting to see inside the actual DPF for the late 2.0 TDI.
People say the engine is built like a brick []house and one should regularly give it full beans. I am always very in-tune with the engine (unintended pun); I hear how its mood changes according to the day. But ultimately if you go for a blast its always happy after that. In fact this really seems to be what the problem is with these DPFs, despite them being connected right to the turbo; they have to get hot and these engines run on the cool side. In normal circumstances a cool running engine will last longer but as I am learning you have to exert your inner devil to imbue the furnace like heat through that can.
There are some chemistries worth looking at. Its hard to say who is doing a better job, but many say the DPF has to be taken off to do a chemical clean. I don't see why that should be the case unless we are saying that no amount of proprietory foam will act on the ash. Not sure why that would be since a manufacturer makes the chemistry for the job. So if you fill your DPF up with a foam chemistry and follow the instructions you should get a result. If these products didn't work plenty of people would be saying so.
Whilst the first 30 seconds of running the engine is the most important time not to aggravate it, it does really need the oil up around 100 degrees before you cane it. The DSG gearbox is sensitive to warming up properly in order to close clearances, but everyone appreciates this, right? And of course you put the best protective nano oil product in the DSG oil, didn't you.
Mannol do a two-part liquid chemical product but as the TDI DPF stands up like a kettle I suspect those liquids are as good as just pouring them into your exhaust pipe. Not sure if you can get Mannol products where you are, but try a foam DPF cleaner and spray it right inside the DPF through the O2 sensor port. Fill it right up until you can get no more in. If you still have some left in the can, wait 30 mins and see if you can get the rest of the contents in. Then it says wait for 20 mins. I'm not sure why I feel that's optimistic. After all the stuff might be really wicked. Make it an hour & in my opinion you should be good to go. Judging from the net, I'm sure you have read articles about various approaches to cleaning the DPF. They invariably say drive the car at 2500-3000 rpm.
FInally, an aircraft engineer I was talking to said that the VAG gearboxes tend to change gear really early and rely on torque to pull the low rpm and that this isn't really a very good idea when first starting out when the engine is cold. He prefers to start the local part of his journey in S. I can see why this avoids cold combustion /fuel products depositing on parts, but you can actually put a little more sense into the drive if you put the box in manual mode. You eliminate unnecessary changes and you can charge the engine nicely to ensure it warms without lugging. Now, I know full well people will say VAG designed everything conservatively and know what they are doing so just leaving it in D is fine. Maybe that's true, but the VAG dealers round my way don't appear to know much. You can bring them a problem like blocked DPF and instead of trying to help you by thinking outside the box they say 'you need a new DPF'. You ask if they can clean it and they say no. You ask how much it will be and they say about a grand. You say something they can't hear and look for a different solution.
My DPF light went out and I got out of limp mode eventually. I applied my own tactics after it appeared the garage job didin't work. I used some chemicals in the fuel and kept hammering it in limp mode, pedal to the metal doing 30 is such great fun. No, its truly awful because there's no fluidity in your drive when you lose the flexibiity power provides. I'd say try the foam and put a good product in your fuel and make sure you drive until its hot. Keep that up and I'm sure you'll get out of limp mode long as you haven't been driving for months on end like that. Keep us posted here as to your experiments and outcomes. Its a subject that many more people are waking up to as the vehicles get older and the dealers try to sting them for big money.
Hi, thanks for the input and info which is pretty comprehensive. Firstly, with the exception of the Superb which I purchased recently, all my other vehicles are manual. Admittedly, running a small taxi company certain vehicles only do short local work but the rest do get a regular blast up the motorway. In addition the ironic thing is my Octavia, the one which is giving the issues, doesn't and never has, gone into limp mode. Even with the DPF light on it pulls like a train right through the rev range and will always red line! I think I will take your advice and search out the 'foam' type of cleaner rather than the liquid sort and give that a go.
You can say, "outhouse" here. Hell, you can even say "shit-house".
I'm not sure I buy into that theory. Cold engines do not like to be revved.
-Uwe-
I'm obliged sirYou can say, "outhouse" here. Hell, you can even say "shit-house".
I'm not sure I buy into that theory. Cold engines do not like to be revved.
-Uwe-
Just thinking of the children who want to know all about VCDS, as everyone should of course!Yes, you are right. Again. To clarify for readers, it doesn't mean putting the vehicle in S for the first part of the drive and driving like you stole it.
As it was explained to me, there are some very small oilways in some parts, and higher revs when cold risks reducing the oil film across bearing surfaces breaking through, when actually you need the volume under pressure to keep parts from touching oneanother. Think of the oil as a liquid spacer.
As almost all your vehicles are manual Ronnie, no doubt you'll be able to draw something from this guidance which I just wanted to give to those with DSG who are asking the question how best to protect the engine when cold. It was good Uwe caused me to elaborate a little on the use of S! And hopefully staving off or preventing the DPF light.
So D, S or M? For those a bit confused at this point, be sensible. If you want to avoid the early gear changes, especially in town, at least initially, or when the engine is cold, you may want to choose D but select the manual option; if you have paddles its a breeze. Just change gear at 2000 rather than 1600 and that should stop that 1200 rpm business, which to many will not feel right I'm sure. VAG have incorporated so many clever features in their vehicles, but not an algorithm for the gearbox that alters the change speeds according to the engine temperature. I am not qualified to say, but they may say this guidance is 'nicht nötig'.
For DSG & Auto owners, maybe Ross-Tech will in future provide a means to get into the DSG controller to reset those shift intervals. However, these cranks are beautifully balanced and they are tough as tanks if you don't act like an idiot. I guess this is a complicated, perhaps controversial subject, and, as Uwe alluded to, you can understand it can't really be just universall advice, like put it in S and go [like a bat out of hell because that's better than D, right?]; No it has to be taken with a large pinch of common sense. This is my formula:
When cold, always wait 30 seconds before driving off. I cringe every time I see someone start their car in the morning, clearly late, and just gas it from the get-go. Wait. Always wait, then select the manual option and change as it feels 'right' at around 2000, change to a higher gear on the downgrade and back up one on the upgrade. Lugging is also not good for the engine.
When warm, leave in D, unless you're driving round town, in which case, I use S. It delays and thus reduces unnecessary shifts and, it is suggested to me, results in higher and hotter gas flow to help with this DPF problem that afflicts so many as the mileages rack up. Cold goo is sticky as glue!
That's about as simple as I can make it. If you listen to your engine as I do, you will notice he always tells you how he feels. If you take notice what he is saying, I don't think you can go far wrong. VAG engines will last a very long time with that little bit of extra care.
Regarding your scenario Ronnie, as you havent actually been forced into limp mode, we need to prevent that as its such a headache, but the dreaded limp will get you if you dont take quick and radical action. If I'm ciorrect, the garage DPF service didn't seem to work for you either, so try this:
DPF additive in fuel.
Fully foam up the inside of the DPF so you can get no more in, even after resting the process for 30 minutes - Dont keep spraying if the foam is escaping. DPF must be below 40C.
Allow to rest for another hour.
Drive straight away after this treatment, holding a steady 2500-3000 rpm for at least 60 miles without stopping.
If DPF light does not extinguish after 150 miles of driving like this (not necessarily all in one journey!), then you should look in your VCDS kit for static regeneration. If that function does not work you'll need to take your laptop for a ride (bearing in mind you must not be distracted) and use regeneration whilst driving. There seem to be two powerful functions for this inside VCDS. Its good we have those codes for accessing that. If they do not help, you may well need to remove the can and take it to the bathroom when your partner isn't looking! Some brilliant videos on DIY DPF cleaning online. But taking the damn thing off is the last thing you want to do.
Let us know how you get on with these tips and tricks and share any of your own here. I'm sure many will find it informative and help us all avoid the stealers.
Agreed, but modern drive-by-wire engine management systems really don't allow damaging lugging. Even with a manual transmission, they simply won't open the throttle far enough (gasoline engine) or inject enough fuel (diesel engine) to cause what we used to call "lugging".
What's that? Way back the early 1990s, we used to go to lunch fairly regularly with a guy who drove a Volvo 240. I don't recall exactly what engine it had; it was certainly a gasoline-powered one, and most likely a 4-cylinder, with a manual transmission. He used to up-shift it at absurdly low RPM and then give it too much throttle, and the engine would protest this in a manner that one could both hear and feel, but he didn't seem to care.
I've not been able to reproduce this kind of behavior on any car with drive-by-wire engine management. Floor the pedal at a very low RPM and the engine management will restrict the air or fuel flow until RPMs increase.
+100.
-Uwe-
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They will however request (and make) boost on a gas engine when the same horsepower could be achieved by revving the engine to mid-rpms.
lol, you should drive YP's Alltrack sometime. There may be 4 cylinder VAGs where the calibration was done well enough that you're not encountering this issue (I'm thinking 2.0T in your A3 and R). That 1.8TSI is not one of them.
I have a convenient and safe hill (~ 8%) near home which sees my occasional Italian tuneups (just to confirm engine OK on full demand). Subjectively delaying flooring the gas just a few 100s rpm until about 1700 rpm after an immediate sharp turn (? 1300rpm) seems smoother and not slower. But maybe just in my mind used to smooth throttle application on old school motorbikes which wanted to kill you otherwise.
Lugging is something else and just doesn't happen.
The reason I would not thrash a cold engine is because even with modern multigrades, the viscosity might not be at optimum, the fueling will not be at optimum compared with an engine at correct running temperature, but most importantly all the components in the power train can be affected by expansion and therefore will not be at the best clearances.
Regards HMC
Regards HMC
This is absolutely correct and really is the best bottom-line explanation why you should not drive it like you stole it until its properly warm. Always, always warm first. The best thing you can do is put your MFD to oil temperature and wait until you reach 100C before you drive hard or at high rpm.
I think I've only ever had an oil temperature of 100c once. Certainly it's usually about 92 or thereabouts.
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Have you reset the dpf to zero before ? It happens a lot when people want to sell the cars with dpf problems , they are resetting the dpf to zero and the car works for few days, weeks, maybe couple of months. However , the ash content is almost to "brick" consistency after a while and problems start showing up : the dpf won t regenerate , limp mode/power loss...You have to consider the fact that if you chemically cleaned the dpf , the properties of said dpf are depleted/tubes broken from high power water jets , etc etc. However , even if you clean the dpf , you have to realize that it wont be clean as a whistle and resseting it to zero it will only aggravate the problem as the ecu will not regenerate in "full " the cleaned dpf.I see these problem almost every other day here in Romania.
I very much agree with this, except I would quibble over the definition of "properly warm". Oil temperatures do vary by engine type. Look to see what's normal, and wait to get most of the way there before thrashing it.
-Uwe-
That is interesting to note after another member said he'd rarely seen 100C on his oil temp MFD. I guess best keep an eye on your oil temp and note where you get to after say five miles of driving average speed. You can do it in your neighbourhood or on the motorway. Then you have a proper idea what oil temp your engine runs.
Another interesting comment there from someone with experience of fudging the DPF. I had a DPF clean by a national garage chain using a special machine that uses hydrogen. I saw only a modest amount of smoke coming out and wasn't convinced. In fact it did not appear to work. It didn't work immediately but the car started to drive faster in limp mode than it had been. I stopped at a services and when I restarted the problem was gone. On chekcing it appears the garage must have reset the DPF. However, having driven it now for a couple of thousand miles and used VCDS several times to check up on it, it seems to be genuinely clean as the ECU has not recalculated more soot and ash and put the numbers back up and back pressure is in the bottom end of normal range. This gives me to believe there are circumstances where such cleans are effective. Any other members had similar DPF experience or used a clean that might have information on their own experience would be welcome to hear. We must know everything here because as many will know VAG tell nothing of the secrets in their systems. I have an inkling that the people in Romania doing the resetting aren't doing it after a DPF cleaning of any sort! It would be interesting to hear from members who have cleaned their own DPF with chemicals both in situ and off the vehicle. Steven B Tuner (Ha!) has some great videos. Well worth watching. He describes how to do it yourself at home; he ran a marvellous set of tests of various commonly available chemicals to see what was effective without causing damage (using glasses from the kitchen when wife wasn't about!). DPF's fascinate me at present and more so when Uwe asked me how my DPF was showing zero ash! I'm still watching to see when the ash figure starts rising again. And of course I am a little sceptical about whether that company should have set ash to zero, like a new DPF, but if you watch Steven B Tuner, you will note he does indeed completely remove ash.
I would think so. It isn't common on cars here in the USA because we have so few diesel cars, but there are sveral million heavy-duty diesel trucks on our roads. Most of them have DPFs now, unless they are quite old, and some states require DPFs to be retrofit even on very old tucks. Many of these trucks are driven 100,000 or more miles every year, some quite a bit more. When their DPFs clog up, they generally get professionally cleaned, not replaced.
-Uwe-
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When we have had a DPF professionally cleaned (we refuse to fit aftermarket types) we always have to do a forced reign after and we also fit and calibrate a new genuine sensor and reset the ash mass to 25% of the maximum value as a cleaned one cannot be considered as good as new. When we get people who seem to be suffering DPF clogging we ask them to run Shell V Power diesel and it really seems to help.
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