Exhaust System Dpf trouble from dealer

Discussion in '8th Generation (2008-2015) [Acura TSX]' started by Stickmanchris, Friday 4th Dec, 2015.

  1. Stickmanchris Junior Member ☆ ☆ ☆ ☆ ☆

    United Kingdom Chris Glasgow
    Hi guys,

    I'm new to the club, wanted to share my recent experience with my DPF unit and my journey to fix it in the hope your advice can help me find a solution. I've read the posts regarding fixes, cleaning,replacements, removals etc and used these throughout my recent problems.

    I bought my Honda Accord 2.2 exgt around 8 months ago (58 plate, bought private) it had done 71,000 miles. It had been driving like a dream up until 10 weeks ago. I came out at a junction and dropped a gear to get up to speed, on accelerating suddenly my DPF light came on and the car went into limp mode. (Icon with exclamation mark) I took the car to my Honda dealer who charged £85 pounds to run a diagnostics and regenerate the DPF. The car was fine for a couple of weeks then same thing happened again, accelerating on the expressway and the light comes on again and limp mode. Back to the dealer they force a regen and charge me again. two weeks pass and the light and limp mode come on again. I thought it might be worth looking to clean the DPF and get a second opinion. took it to an independent Honda specialist who deals in tuning. They ran a diagnostics and where confused as soot levels where at 26%. I was of the understanding that limp mode should only be on if the DPF is clogged or at around 60-80%? They put cleaning fluid through the fuel and tried to run a regen but the software they had wasn't up to date. They suggested the dealer would have the most up to date software and advised that the car should be showing a DPF icon to allow me to drive at hi revs for sometime (as shown in the manual) to force a regen myself before going into limp mode especially at such low soot levels.

    I returned to the Honda dealer and explained my findings that the soot levels where low and what was there diagnosis on it, they charged me a further £42 to check the soot levels, now 33% and where successful in regeneration, switching the light off. They did however say that if it happens again they would only replace the full DPF unit and won't regen. I'm now in a massive predicament, the light came on AGAIN and is in limp mode...I have a few questions I'm hoping you guys can help with:

    1: if soot levels are so low should the warning light for me to regen it myself through driving not be coming on first before entering limp mode? And if so could it be that it's a sensor or problem there rather than a full DPF replacement?

    2: Honda are suggesting a replacement but if the DPF is only 33% soot levels does that not suggest the unit is fully functioning?

    3: I have looked at removal of the unit but worried it may fail an MOT especially in light of the recent VAG fiasco and equally worried that I would use an independent that might not carry out the job well enough.

    4:has anyone has similar issues and found a solution? I.e low soot with repeated limp mode?

    5: could the sudden erratic acceleration have anything to do with tripping sensor?

    I'm unsure of how to rectify the problem, the dealer suggested around £1200-1600 to replace the unit. I wondered if it's worth sourcing the OEM part myself them paying the dealer to fit it to save money? Also do you think it's worth sticking with the dealer for the work as there will be a better warranty should the light some back on or would the part itself be the only warranty therefore a local could fit it for cheaper?

    I know I'm asking a lot guys and throwing a lot of info into the mix but I'm at my wits end on this one and it's taken all the fun out of what was supposed to be a great driving experience.

    How you guys can help.
  2. dbrooks65 Valued Contributor ★ ★ ★ ☆ ☆

    Scotland Dave glasgow
    Chris, I'm sure there will be more technical guys than me along soon with some input.

    I had the same experience with a previous Mazda - although I'm not sure what the soot levels were - just that it required DPF regen after regen even although most of my driving is up and down the M8. Very frustrating so I sympathise with your predicament.

    Have you read the posts about only using low SAPS engine oil for servicing and filling up with premium diesel?
  3. Stickmanchris Junior Member ☆ ☆ ☆ ☆ ☆

    United Kingdom Chris Glasgow
    Hi dbrooks65,

    Thanks for your sympathy, it really is a nightmare, yeah I read up on this too, I had them check the oil for me and they clarified it was low SAPS, I also checked what oil had been put in on the previous services too. Since the first DPF light came on I've been using premium diesel too and hoped that might do the trick but still no luck :-(
  4. Kristian Club Member ★ ☆ ☆ ☆ ☆

    Norway Kristian Stokmarknes
    Chris, did you read through the I-DTEC regeneration thread?
    I experienced pretty much the same you are going through right now, and given your mileage your best solution is most likely a spanking new DPF. I posted my solution here:

    As for soot levels given in percent, I am pretty sure the value of 26 given to you was in fact grams of soot estimated to rest in your DPF (PM/particulate matter). The DPF does not, as to my best knowledge, operate with blockage parameters given in percent. The latest firmware installed in your car tells your car to initiate DPF regeneration when the PM value reaches 12.5 grams. Up until this point, all your DPF does is collect soot. If your car has too many short journeys around this given value, it will never manage to regenerate and will ultimately reach a PM value of 25 grams. When this value is reached, your car will go into limp mode without any pre-warning.

    The thing I came to learn during my conversations with Honda Norway, was that DPF's like any other filter, has a given lifespan/mileage. The natural regeneration process your car usually would perform every 800-1200km never completely manages to rinse out the DPF. For every regen there is remaining soot. Your car will think it is all cleared out, as the estimated PM values are set to 0 grams. PM is calculated by two pressure sensors; one in front of and one in the back of the DPF. During everyday normal driving without any hard acceleration, your PM value will more or less increase at a steady rate. With hard acceleration DPF pressure gets a sudden increase and estimated PM value might go from 10-11grams to 25grams in seconds, and limp mode is inevitable. Remaining soot in your DPF is to blame for the sudden increase. Given your mileage, the only long term solution is a replacement.

    I experienced "DPF!" at 106k, 122k, 129k and the last one just 900km later. My car was at this point unable to regnerate at its own, due to high remaining PM. Since the DPF replacement (6 months/9000km) my driving has been trouble free! Chemical treatment, forced regens and so on is only going to set you back unnecessary money and postpone the inevitable replacement.
    I would strongly suggest sticking with authorized Honda dealers (as opposed to unautorized shops) for both forced regens as well as DPF replacement, as they posess Honda Diagnostic Software/System.
    - - - Updated - - -
    Limp mode is activated at a PM value of 25 grams, if that was not clear enough in the prior post. By the time you get to the dealer/shop it has likely increased to 26 grams due to the miles driven since limp mode was activated. The last two forced regens I had on my car showed a PM vaulue of 26.1 grams.
    John Hamer, Nels and Zebster like this.
  5. Stickmanchris Junior Member ☆ ☆ ☆ ☆ ☆

    United Kingdom Chris Glasgow
    thanks Kristian for your information, I've had a read through pretty much every post on here to best get myself informed before speaking further with the dealership. Done some more digging through my previous services and paperwork, turns out at the last service (71,000 miles a month before i purchased the car) the dealer carried out an oil change and filled it with 5W 30!! Update is I've had around 5-6 calls with Honda Uk explaining that the oil should have been 0w 30 and that it wouldn't seem unreasonable that the failure could be down to the wrong oil. As i said i checked through all previous posts and found the Honda Bulletin that states:

    "Honda(UK) strongly recommends the use of 0W/30 fully synthetic lubricants that meet ACEA A5/B5 specification for I-CTDI engines and ACEA C2/C3 for I-DTEC engines as fitted to the 2009 Accord models. Failure to use this new specification of oil in cars equipped with a DPF can result in premature failure"

    I explained this to Honda and their technical team said its not the wrong oil and has no bearing on my now failing DPF. The car has only ever been serviced by Honda dealers,no previous issues with the DPF have been present until the incorrect oil was placed in it by a registered Honda dealer, the DPF has now failed. If the oil is only a recommendation then why are Honda dealerships not using the recommended oil of 0w 30 that ensures the following according to your documentation:

    Customer peace of mind - Improved fuel economy - Reduced environmental emissions - Increased engine protection

    This seems simple enough to me:
    HONDA RECOMMENDS 0W 30 to avoid issues with DPF blockage and premature failure
    HONDA then ignores this and puts 5w 30 in my car and then the DPF fails.
    Surely they should admit liabailtiy and suggest rectifying the issue with a replacement DPF and oil change?

    I don't see why, what can only be described as a cost cutting exercise by Honda Dealerships to use an alternative oil should result in me having to suffer reliability issues and financial hardship though trying to fix an issue which is known to be caused by not using 0w 30 oil.

    Im awaiting word back from the customer services and unfortunately left with out a drivable car over Christmas :-(
    really disappointed in Hondas service its been weeks since i initially discovered the issue and visited them and 2 weeks of phone calls with still no solution.
  6. Zebster Guest

    I don't understand how use of 5w-30 instead of 0w-30 could cause a DPF problem?
  7. Stickmanchris Junior Member ☆ ☆ ☆ ☆ ☆

    United Kingdom Chris Glasgow
    Hi Zebster, i could be mistaken but all recommendations on this forum point at only using a 0w 30 low saps oil or you'll encounter issues with blockages, i read through over 30 pages of posts. also the Castrol leaflet accompanying my manual suggests only 0w 30 is suitable for my model and the Honda bulletin also says 0w 30 for 2.2 diesel Accords. I understand mileage can lead to blockages too but am i right in thinking that using 5w 30 can increase chances of a blockage especially with stop start journeys? Zebster id be interested to hear your thoughts on my current situation, having expert advisor status anything you can provide knowledge on would be appreciated.
  8. Zebster Guest

    An oil with a 0w cold rating will give a better oil flow than a 5w at cold temperature start-ups, which is a benefit to engine bearings, etc.. But the low SAPS advice is highly relevant for a vehicle fitted with a DPF to avoid a build up of material that cannot be cleared by the usual regeneration process. These are unconnected issues.

    So far as I recall, 'Expert Advisor' status is granted to HK members who have made more than 1000 posts, so perhaps a little misleading! I do not know why some DPFs fail early and for no apparent reason... I can only speculate that fuel contamination at some point during the vehicle's life may have caused damage to the internal surfaces of the DPF?

    I'm going to be controversial (others will disagree!) and suggest that a much cheaper alternative to DPF replacement would be cartridge removal and an accompanying ECU remap. You should get improved performance and/or MPG as an additional benefit, but may have problems if future MOT emission testing was to become more stringent.
  9. chunkymonkey Senior Member ★ ★ ☆ ☆ ☆

    United Kingdom Gary Lincs
    Just to add my Mrs had her cambelt done on her Leon- please don't shoot me for swearing by mentioning a VAG product! Anyway spoke to the bloke at the specialist and they have invested a decent sum of cash in a cleaner, they take the DPF off the car wash it through and then bath it in chemicals before washing through again then fit it back on the car they say its very successful, best of all it was around £225 to have it done. Not sure if anyone else has heard of this but just thought i would add it to this post.
    Zebster likes this.
  10. Zebster Guest

    I guess it's worth a try!
  11. chunkymonkey Senior Member ★ ★ ☆ ☆ ☆

    United Kingdom Gary Lincs
    That what I thought Seb, even if you get say another 18 months out of it surely its worth it?