Guys,

 

just wondering if any one has had issues with dpf on 170 CR TDi.

My 62 plate vRS has been mapped (custom map that is) and also egr delete as after map I had some issues with eml. So couple of months after map i had egr delete done which cured eml.

Now what I didn't realise is that the egr helps with the dpf regens by increasing temp of exhaust gases and helps reduce the amount of soot going in to dpf. I'm not sure mine is doing regen properly and seems the block up quite quickly. Now i must admit my commute to work probably doesn't help matters as no motorway miles to speak of. Car is serviced every 10k using proper vag oil and parts, also use bp ulimate derv too. Part of me feels like getting dpf ripped out but that is dangerous territory with regards to MOT and future resale and would probably smoke like fook! 306 dturbo style!! I have had few carbon cleans done which helps for a while. Any advice would be appreciated, thanks. I feel like going back to standard tune, but I would miss 220bhp and 356 fl/lb ;-)

Edited 7 January, 20188 yr by mrlucky09

I have similar thoughts as you since looking into dpf and regens on a Yeti with the ECU fix. 

 

This is my question and it can only be answered by whoever made your tuning map: It is possible if you ask, to have a stage 1 remap tune leaving all the emissions components in place. I know this works and you might lose a few horsepower. The EGR and regeneration functions for the dpf are still active, as are all the dash warnings if there's a fault.

 

After a tune you increase mass air flow and the stock emission system uses this (and dpf pressure drop) to calculate the regen. intervals. More mass air flow = dpf regen. more often. but what has the mapping done? If dpf regen. is disabled the dpf will just get full of soot. You may no longer get a MIL or dpf warning, but sooner or later you will have to do a dpf bypass. The ECU tuners appear to sell options like sweets in a sweetie shop. but IMHO you can't just pick this and that or what you can afford. You either do the whole lot with questionable legality or keep all the emissions components operational whilst accepting the extra horses may reduce dpf life longer term due to higher mass air flow and more soot. There is a caveat that a good tune can be more efficient and deliver better economy. In that case, the dpf soot load may not be much different to the stock 'general purpose' level of tune and will stay that way if normal regens are occurring.  By 'normal' I mean at the intervals calculated by the sensors and for the duration and high temperature needed in the dpf for it to work. An effective regen. cycle needs high temperatures to be reached in the dpf and this can only be done with all the emissions components working.

 

I think an unfortunate side of having ECU remaps done is many do not fully understand how the stock emission control system is going to work (if at all) afterwards. They take the easy step of blanking of the EGR valve and have the warning lamps tricked out, but what is going on in the remap? A good tuner will understand all these things and should explain exactly how your engine will work afterwards. My suspicion in your case is your dpf soot level will rise faster and even faster without proper regens taking place. You can check this out with diagnostics. It might be fooled telling you that regens have taken place, but with an EGR delete I suspect your dpf ash and soot levels will be going up. Tuners can trick the dpf warning but the soot and ash levels and pressure drop readings will probably still tell the truth. If you try to go back to EGR 'off' or a Stealer does a re-flash to stock, your dash will probably light up like a Christmas tree with MIL and emissions faults, then limp home mode!

 

Just my 10 cents, but I think a Stage 1 remap keeping all the OE components and controls is your best bet if you haven't already stuffed your dpf with soot! AND you must know exactly what your remap is doing.

I’m currently suffering with the same issue as you but on the ppd170 engine, iv had a remap done and egr delete done due to leaking egr cooler and now my car won’t do the dpf regen as there is a hidden egr fault, so iv left it with the place that did the map for me to fix, hopefully they can remove the egr error P1443 witch does not bring up the dash error but shows on scans, once this is removed properly I hope that then the dpf will finally regen before it’s totally knackard, if not I’m cutting the dame thing off lol

I would tend to underestimate their tuning skills as being limited to putting ticks in the software boxes calculating the new checksum and pressing 'do It'. Unless you are dealing with a high end pro race tune shop, I doubt most tuners really understand the OE design and how it integrates all the emission control functions?  I suspect you can have simple options like EGR delete, T.V always fully open, timing changes, cam changes, warnings disabled etc and then they might do a dyno test. But if they are a small outfit or bedroom tuner, they will rely on what the software in their tuning file tells them to produce those pretty torque and horsepower curves. Once you start asking for some parts of the emission design to work and not others (i.e do effective regens.) I doubt those options will be there because they will have tricked the exhaust gas and MAF sensor outputs to stop warnings. Which is why I suggest there is no half way? You either tune for torque and HP keeping the emission controls as is, or remove the lot and consider legality. It is a real conundrum and there isn't a cheap quick way back from the last option. Most Stage 1 tunes claim better fuel efficiency, but I've seen no evidence of the regen. cycle being changed from stock after the tune. The priority selling point for tuning is output and fuel economy, not pouring fuel into a dpf to get it hot!

 

My next trial venture is to remap a spare ECU starting with a generic map and keep all the existing emissions functions. Swapping back to the stock ECU isn't too difficult, the hardest part is removing the wiper arms, but that is a lot easier than replacing the dpf and EGR cooler assembly! There are some issues I have to discover:  Any variable data stored in ECU non-volatile memory won't stay in sync with miles driven after ECUs are switched. This data includes ECU mileage and dpf values. E.g you've been running with a tuned ECU for a year, then swap over to a stock version sat unused on a shelf. Will the ECU re-learn its variables or take the new pressure drop on the dpf, work out there is inconsistency and something is wrong. Anybody who has not removed emissions parts and had a Stealer wipe an ECU re-map back to stock will probably have the answer?

 

I think the biggest problem with remaps failing is they are done after an engine is already gummed up.  The extra soot load causes parts to fail that would have failed anyway, but not so soon. I've read a 100K miles is the expected life of the dpf and other parts. I have a VAG vehicle at 50k miles with a dpf ash load around 34% which I'm keeping an eye on. Ash doesn't go away with regeneration and when it trips the V.W limit it's 'light on take to garage' and regen. might be impossible. If your dpf has done 50k miles and your soot and ash loads go up (or you have the EA189 fix?), my gut feeling is a 75k miles expectation for the dpf with other key parts likely to fail faster. A decent tuning firm should co-operate to give you the tune option choices best for you, but they won't be responsible for what a worn engine might do after tuning.  I suspect they will always recommend the dentist way - extract the parts and trick the ECU.

 

 

Thanks for the replies guys, to be honest i got the egr delete done without thinking about the potential consequences. Anyway, I did take my car for a longer drive at constant speed to finish active regen, it seemed to work ok. I understand that soot will build up quicker, but maybe if the regen can be completed more often with a bit of luck my dpf might not soot up quite as bad. I think part of my issue is that recently I haven't been able to complete a regen properly due to the time of mileage I do commuting.

Quote

I think part of my issue is that recently I haven't been able to complete a regen properly due to the time of mileage I do commuting.

 

You are not alone, we are also low mileage short journey drivers, which is why the EA189 ECU fix with more frequent regen. requests makes things worse. From now on you will know the signs of incomplete regen. - fans on after parking when the engine is at normal or low temperatures. The Android app will also be helpful to you, although I'm doing something in hardware permanently fitted.

 

I'd never used vcds before to force a manual dpf regen., being kinda worried about some of the caveats and warnings. I now understand vcds can initiate 2 kinds of regen: 1. Idling the car when you need plenty of space around it and fire extinguisher handy. and 2. You initiate the regen, with the engine at normal temperature, dpf warning lamp comes on, drive for 15-20 minutes @ 2-2.5k rpm until the dpf warning goes out and job done. 

 

I'd have no hesitation in repeating option 2 on a more regular basis. The dpf temperature rises under control whilst driving and there is plenty of air moving through the engine bay. When the dpf light goes, out you get immediate confirmation feedback that the regen. has completed. Something V.W should have built in from the start. But we can guess they didn't do this for risk of scaring away potential diesel car buyers. Now they have reduced the time between dpf regens with the EA189 ECU fix it is even more important to know when your dpf is regenerating and it finishes o.k.

 

If there is plenty of discussion about dpf regen., it won't be long before the Chinese produce an OBD II dongle you just plug to send VAG specific start codes to start a regen. Although Ross-Tech vcds does suggest you should monitor exhaust gas temperatures.

 

 

 

 

On 08/01/2018 at 13:41, mrlucky09 said:

Thanks for the replies guys, to be honest i got the egr delete done without thinking about the potential consequences. Anyway, I did take my car for a longer drive at constant speed to finish active regen, it seemed to work ok. I understand that soot will build up quicker, but maybe if the regen can be completed more often with a bit of luck my dpf might not soot up quite as bad. I think part of my issue is that recently I haven't been able to complete a regen properly due to the time of mileage I do commuting.

 

Did you remove the egr valve or just have it switched off in the ecu ? I ask as I had it switched off in the map but then done the dark side delete egr witch left a hidden only visible with vcds error witch stopped my dpf regen, 

 

recently fixed this by just plugged the egr valve in to clear the code and activated dpf regen and it worked just left the egr cable tied to boost pipe while drove ro7nd doing regen 

it was egr delete off the map, but egr still in place so to speak. 

You cannot remove the EGR from the system without upsetting the DPF.

The EGR forces the un-burnt mix after being cooled round the engine again which gives a lower ash level. with it removed you will find in a short space of time if not long distance driving that the DPF will fail regens alot due to the quick build up of ash.

Even if you take it for a run to regen it will still  weaken the lubrication around the engine causing a shorter engine life brought on even more if the remap is poorly done. More frequent oil changes should be done & a close eye on oil level / quality.

 

 

7 hours ago, Busamad said:

You cannot remove the EGR from the system without upsetting the DPF.

The EGR forces the un-burnt mix after being cooled round the engine again which gives a lower ash level. with it removed you will find in a short space of time if not long distance driving that the DPF will fail regens alot due to the quick build up of ash.

Even if you take it for a run to regen it will still  weaken the lubrication around the engine causing a shorter engine life brought on even more if the remap is poorly done. More frequent oil changes should be done & a close eye on oil level / quality.

 

 

 

 

#Crap I think I reported your reply rather then quote so sorry #

 

what I meant to say was 

 

if this reply is for me yea I found out the hard way, darkside were more then willing to help with info on sorting my issue so I could go back to the mapper to try and resolve my issue, witch with the info they gave me just simple plugging my egr back to the car it sorted my issue out so I’ll be removed the egr delete and fitting my egr back on with a black fitted as I removed the cooler as it was leaking 

On ‎07‎/‎01‎/‎2018 at 09:59, mrlucky09 said:

Now what I didn't realise is that the egr helps with the dpf regens by increasing temp of exhaust gases and helps reduce the amount of soot going in to dpf

 

Where did you learn this? My understanding is that the situation is almost the opposite.

 

 

8 hours ago, Busamad said:

The EGR forces the un-burnt mix after being cooled round the engine again which gives a lower ash level.

That's not what EGR systems do at all, but is a common misunderstanding. It's not about 'having another go at combustion to clean up unburnt stuff'; it's about changing what goes into the combustion chamber so that not so much NOx is created (but more soot tends to be).

 

 

 

 

Summarizing the discussions in this thread so far:

 

IMHO the issue is those that have had remaps and deletes done don't really know what is still going on if original parts are left in place? I said earlier that there were only 2 ways to go: Keep everything working and lose a small amount of horsepower, but watch for increased ash levels and expect a shorter dpf life, or tear everything out and consider the legals.

 

If you can't trust your mapper to tell you or maybe they can't be sure? Use the Android App or vagcom vcds to see what's going on. I think you can only force trigger the start of a dpf regen. cycle (if it will start?) with vcds to know that it is running (dpf dash warning lit during cycle). Look at the dpf temperatures which should be reaching at least 700C for 10-15 minutes. You can check the soot and ash levels before and after.  Vcds tells you the mileage and engine running time since the last regen, but that could be fake data after a re-map, so it's better to trust temperature readings? I could explain how to do this by monitoring the dpf EG sensor, but it would need another thread and I'm nearly ready to assemble and test my hardware based in-car monitor.

 

Re-maps could stop regens whilst interfering with the ECU time/distance logging and not allow the soot and ash levels to update? This is what you would expect from a dpf/EGR delete because the engine components wouldn't be there and the dpf pressure sensors output would be masked to stop warnings.  So why allow automatic regens at all or anything to do with a regen to set a fault warning? If you chose those remap options and decided not to remove parts, you bring on all kinds of problems later on with inevitable blocking of the dpf.

 

If you have had any kind of re-map done, you should monitor the dpf exhaust gas temperature to be absolutely sure you are still getting automatic re-generations, or not getting them if you have removed engine components. I don't see a half way house pick and mix option for a remap.

I started another topic on this earlier, I just got remapped for the economy side of things great economy though never removed any of the egr or DPF but now the thing is constantly regenerating the minute you press the accelerator 

I can only say Stage 1 works for the older non-CR PD engine without removing anything. This may not be you, but I warned a long time ago that many remap tuning files had been done before the ECU fix came out and anybody doing a remap on a 'fixed' engine should be careful, because most of the tuning files modify the fueling code blocks and leave the rest of the code alone, but that is what V.W/Skoda will have modified to apply their fix. Many so called 'tuners' haven't got a clue about the background workings of the ECU and the (complex) engine management code. You can only trust a tuning file when it has been properly tested with the code in your ECU if it has been modified. There are loads of tuning files out there made by DIYers and the pro tuning firms. But even they may not know exactly how the tuning remap they apply may work out in practice?

 

Any tuning firm worth dealing with will have copied your original stock file before applying their tune and it should be that file you can revert back to. Unfortunately, many tuning firms won't give you that 'before tune' file after modifying your ECU - you have to ask for it. Without it you have no insurance to go back and you are in their hands to do it and charge, or the firm may go bust some time ahead when you might need it.

 

The safest way to go might be starting with a 'vanilla' tune file that corresponds to your VIN when the car was built. This should be mostly the same as the file copied before a tune if the ECU mod wasn't done? Taking it in steps, you could have the vanilla file installed and check everything runs as you expect and move to the Stage tune using that file.

 

I haven't seen much credible info coming back here from 'tuners' as to whether they really know what effect their tune might be having on the background functions. I do wonder about some things. Let's say you had a 'vanilla' back to OE pre fix file applied. How is the engine management for dpf regen going to react if the old data re dpf soot and ash levels isn't carried over and it thinks a new dpf has been installed, but the pressure drop values are those for a clear dpf and not one that has done some miles? Then there is other data stored in ECUs like the ECU mileage. Has the original ECU personality stored before the tune been carried over to the new tuning files?

 

I think you are at the mercy of the tuner to sort out your problem. One last thing: If the tune sees a dpf it expects to be clear but has soot and ash, it might be trying to do a first full regeneration which could take 20 minutes over 40 mph and above 2k rpm. If the dpf regen light is coming on, your car is saying it needs to do a full regen., perhaps to re calibrate itself to your used dpf? It is an unusual event to get the dpf warning on with mixed long and short journey driving. I've done a  'forced' driving re-gen. using vcds and the dpf light behaves as you say until after the 20 minute drive it goes off. If the journey is too short I think the stupid system keeps trying again. If you find your engine fans are running on after a journey in cool weather, that is a clue that dpf regen. has not completed.

 

If you had done your own vcds scan before the tune, you would have all the stored variable data for the ECU like mileage, dpf soot and ash levels and you could then compare that data with what you see after their tune. If the data has been reset to '0' aka a new dpf, or worse they put in the wrong file file for a dpf remove, I think you can expect problems.

22 hours ago, JacksVRS said:

I started another topic on this earlier, I just got remapped for the economy side of things great economy though never removed any of the egr or DPF but now the thing is constantly regenerating the minute you press the accelerator 

 

We got a REVO map done a while ago and had to get a new DMF and clutch as there was slipping, EGR cleaned out, turbo refurbished and DPF cleaned out. Cost a klondike but has been ok since although it also does regenerations every week or so. It still pulls like a train and economy is mid to high 40's running about and low 50's on a run.

 

Just for info, the EGR does not increase exhaust gas temps but introduces combustion gases back into the combustion chamber to lower combustion temperatures. Oxides of nitrogen (Nox) are produced at temps over 1800 deg C and the EGR replaces some of the clean air with burnt gases to lower the temps to minimise this.

16 minutes ago, FatblokeVRS said:

 

We got a REVO map done a while ago and had to get a new DMF and clutch as there was slipping, EGR cleaned out, turbo refurbished and DPF cleaned out. Cost a klondike but has been ok since although it also does regenerations every week or so. It still pulls like a train and economy is mid to high 40's running about and low 50's on a run.

 

Just for info, the EGR does not increase exhaust gas temps but introduces combustion gases back into the combustion chamber to lower combustion temperatures. Oxides of nitrogen (Nox) are produced at temps over 1800 deg C and the EGR replaces some of the clean air with burnt gases to lower the temps to minimise this.

It's unfortunate you had that much trouble, mine has 107000miles and funny dpf seems OK at the minute again but never had any clutch or turbo faults yet, as I said it's for the economy, but I hope it doesn't become a money pit. Would you remap again?

Edited 15 March, 20188 yr by JacksVRS

Mines a pd170 btw

21 hours ago, JacksVRS said:

It's unfortunate you had that much trouble, mine has 107000miles and funny dpf seems OK at the minute again but never had any clutch or turbo faults yet, as I said it's for the economy, but I hope it doesn't become a money pit. Would you remap again?

 

I got my Astravan 1.7 cdti remapped and it was the best thing I ever did. Much better to drive and absolutely no issues.

Traded it in at 105,000 still running sweet and still on original clutch and turbo (oil and filter changes every 5000 miles). No DPF though.

Got an A3 now and would definitely consider a remap after the warranty is out in another couple of years. Will probably go for a custom map next time though.

 

Edited 16 March, 20188 yr by FatblokeVRS

I'd agree, but experiences can be different because a 'remap' at whatever stage is not some standard off the shelf  item and they are not all the same. If you compared the modified hex code from 2 remaps done by different tuners, I bet they wouldn't be the same? If you have vcds the easiest way to compare 2 tunes of the same stage is by looking at the ECU checksum values. This is a unique code calculated from the ECU file. The dealers only have to look at this and compare it with their official OE release values to tell if it's a remap or not. When any of the code is changed, a new different checksum value has to be created, otherwise your ECU program won't run. After each reflash, a count is permanently stored in the ECU

 

The second reason why experiences can differ is how the vehicle is being used. It may not always be the case, but a high mileage trouble free stock or remap tune could be due to long journeys and good dpf regens., whereas a low mileage vehicle (for its year) may have been used for short stop start trips. Whilst a remap may improve mpg for average driving, start pushing for more power, use hard acceleration and the dpf soot load being monitored will rise faster needing more frequent regens. Worst case driving style would be short start-stop journeys with aggressive acceleration, or possible towing where road speeds are restricted. If you tow, consider using a lower gear to keep the tacho at 2k and your dpf should regen. normally in the background above 40 mph. That rather turns on its head the value of paying more to buy an older low mileage used diesel car, unless it spent most of the time in the garage not being driven. Knowing the mileage, dpf soot and particularly ash level for any used diesel car before you buy is a useful indicator of how it has been driven. If the odo mileage has been tricked you are stuffed.

 

For those with diagnostics it would be a useful starter thread to report their mileage, dpf soot and ash levels and how they drive their car - short/long journeys, towing, school runs etc.  At least you can get some idea from the dpf condition how a used car may have been driven (unless the dpf was replaced), which you can't get from a gasoline engine.