Announcement

Collapse
No announcement yet.

Forcing a DPF regen with OBD tools

Collapse
X
  • Filter
  • Time
  • Show
Clear All
new posts

  • #31
    I wonder just what the ECU "upgrade" does then? I will be very interested to hear what ExNissan thinks about this as it was his post about not seeing any passive regeneration on his long travels that made me curious why nothing shows on the % readings unless a burn is happening.
    So just to be clear we think that the ECU computes the % from the fuel and distance, then decides the DPF is full and starts a burn.
    While this burn is taking place the ECU computes the temperature and length of the burn and assumes the DPF is now clear?
    ExNissan explained in post 21 that to get a useful reading from the differential pressure sensor the gas volume would have to be taken into account as well.
    As there is no sensor for this (afaik) then this differential pressure sensor is only used to detect a partial or full blockage?
    Does this mean that we may all be using diesel to heat the DPF to 500 odd degrees when it may not be necessary at all?

    Comment


    • #32
      Originally posted by JohnLynn View Post
      I wonder just what the ECU "upgrade" does then? I will be very interested to hear what ExNissan thinks about this as it was his post about not seeing any passive regeneration on his long travels that made me curious why nothing shows on the % readings unless a burn is happening.
      So just to be clear we think that the ECU computes the % from the fuel and distance, then decides the DPF is full and starts a burn.
      While this burn is taking place the ECU computes the temperature and length of the burn and assumes the DPF is now clear?
      ExNissan explained in post 21 that to get a useful reading from the differential pressure sensor the gas volume would have to be taken into account as well.
      As there is no sensor for this (afaik) then this differential pressure sensor is only used to detect a partial or full blockage?
      Does this mean that we may all be using diesel to heat the DPF to 500 odd degrees when it may not be necessary at all?
      Yes thats correct I believe we are wasting fuel doing unnecessary burns which may actually reduce the life of the filter. Jeeps burn only occurs about every 1500km. The update is supposed to address the problem with DPF temp being too low when driving at 110km/h.

      If you consider how a passive burn would work you would need the DPF temp to raise into the 500 deg plus mark. To attain this you would need to be working the engine pretty hard ie towing. Problem with this is that the towing uses more fuel which counter acts the passive burn.

      There needs to be a better system that removes the soot from the exhaust system. Think Dyson...
      2016 2.8l 6spd Auto Prado Crystal Pearl VX, Dual Battery, Pro Racks, Towbar.

      Comment


      • #33
        Starting to think there is a bug to quick reply where you end up with 2 posts.
        2016 2.8l 6spd Auto Prado Crystal Pearl VX, Dual Battery, Pro Racks, Towbar.

        Comment


        • #34
          Originally posted by cuda View Post
          Starting to think there is a bug to quick reply where you end up with 2 posts.
          I've been getting that too

          Comment


          • #35
            I've got no direct evidence other than my mate who had his DPF go pear shaped while on a trip north, but by his account the system went into limp home mode because of high DPF differential pressure.

            From what I heard from him and following up with the local service manager, 0-100% is normal operation (ie corresponds to certain dP across the DPF). If the dP hits 120% the "see dealer light" comes on, and if the dP hits 180% of normal then the engine goes into self preservation/limp home mode.

            So the CPU must be using the dP from the sensors - but as mentioned, this dP will be a function of how much gas is flowing and at what temperature, which in turn will be a function of RPM, load, throttle setting and temperature of the engine/exhaust etc - which would be very complicated to map.

            Maybe the regen is a simple algorithm based on distance and fuel burned as this was easier to implement, then the protection system uses the dP? And the protection system is not monitoring/figuring anything out, just if it sees an instantaneous dP outside the set points it initiates action?

            Comment


            • #36
              Has anyone set this up on an apple device with a wifi dongle? Was wondering what app you used

              Comment


              • #37
                Cheap IPhone OBD monitor and burn initiator - setup

                So I did some tinkering last night and had some great success. This sort of stuff is pretty new to me, so I thought I would document my journey so if others who are less familiar but want to set up a manual burn backup they can too. If I could do it with stubborn ignorance and get it working, others should be able to too.

                Firstly many thanks to all who have posted above on this thread – would not have got anywhere without the info above.

                My objective was to have something that enables checking what the DPF is doing, and initiate a manual burn if I am out in the bush and the DPF light comes on then clear codes (I had a mate who had his go into limp home mode on a trip). I don’t intend watching/logging it continuously, it does not need to be fancy.

                I decided to go down the plug in ELM 327 wi-fi module with an Iphone app rather than a dedicated scan gauge. Did some research, and it looks like Bluetooth adaptors do not work with Iphones, and there are some older/dodgy ELM 327 types out there. I looked on e-bay, found one that looks a bit more modern and had wi-fi and risked a whole $20 to get one of these: Konnwei KW903 ELM327 https://www.ebay.com.au/sch/i.html?_...LM327&_sacat=0

                Next the app – I had no idea if the adaptor would work, so I started with a couple of free apps as I didn’t want to outlay $15/$50 on an app then not have it talk to the dongle etc. The app “Car Scanner” was free, simple and seemed to have what I wanted so I started with that.

                CONNECTING

                First I opened the garage door so I would not gas myself. Plugged the OBD scanner in, started the car. All OK so far.

                Fired up the wifi in settings and it could see the scanner, but was having trouble connecting. Opened the app, which on the home screen shows a connect button and a ELM and ECU connection status. It was seeing the ELM but not the ECU. The app recommended changing the IP address to the ones shown below in the screen shot – went to the wifi connection in settings on the Iphone, set manual IP and it all came good.



                Next step was identifying the make/model codes to use – I went with Toyota 2010+, and the app was up and working and showing the RPM etc.



                DPF monitoring

                So I went into the gauges part of the app to see what DPF info I could get. There was a long list, which is easy as they are all fairly clearly labelled and you can just scroll through them and then click on them. Scanning down there is the following that were of interest:
                1. Exhaust gas temps 1-4 (as above 1 is directly downstream of the engine, 3 is downstream of the DPF, 4 was not available/no data)
                2. DPF differential pressure
                3. DPF upstream and downstream pressures (would not give any data)


                There was no DPF status %, so I went to setup (gear icon top left on home screen in the app) then custom sensors, then used the data in this thread – basically PID 2138 and formula of J*2. And it worked! It was reporting DPF Status as 34%. As with others DPF status jumped in increments of 2.



                So now I had a custom gauge that showed/graphed DPF status, DPF dP and temperature before and after the DPF.
                Attached Files
                Last edited by LeadWings; 12-01-2018, 02:22 PM.

                Comment


                • #38
                  Cheap IPhone OBD monitor and burn initiator - use

                  All the above was done in the garage with the car idling – so temps were low. So I went for a drive to test it out, and the temperatures climbed to the 300’s. Inlet temperature was more volatile, downstream temperature was more damped/slower responding.

                  DPF dP was negative at idle, and was positive and varied when driving. So I thought I would do an experiment to see if was a nonsense or sensible figure. I figure the dP should be a function of air flow/velocity, so I set up a screen with DPF dP, mass air flow (MAF) and RPM – my car is a manual, so I figured that the flow volume should also be a function of RPM. I know comparing the 3 is simplistic as it will be a function of load, exhaust temperature etc but I was interested to see what came out. Screen shot is below – I was actually surprised how well DPF dP matched MAF.




                  INITIATING A BURN

                  So after driving around for a bit I figured I would see if I could initiate a burn. Was very nervous about this. So drove home, parked in the garage and started playing again.

                  On the home screen there is an icon for “terminal”. Went to this, and just started trying the codes in the first post of this thread.

                  First tried 3029060101. It responded with ODT. Tied it again, and got something back as per screen shots below, but no change in RPM/burn etc. Then tried 07E0 05 30 29 06 01 01 00 00, nothing then tried 3029060101 again and suddenly the RPM jumped to 2000, and the DPF light on the dash began to flash.

                  See screen shots for the conversation with OBD. I would be keen if anyone can shed some light on what the correct entries should have been, because it was obviously trying to communicate back to me and I got it to work by luck and I am not sure if I could do it again reliably!!!!

                  Attached Files

                  Comment


                  • #39
                    Cheap IPhone OBD monitor and burn initiator - burn

                    Went back to the monitoring screen and watched the burn happen (note I was playing with the gauge configuration so they change in the shots below).

                    DPF status on the app was now reading 100%. Normally (mine is a manual) the RPM for a burn is 1200, but this held 2000 for about 2 minutes, then went back to 1200 for the rest.

                    You can see the temperature climb as the burn happens. Max downstream temperature was around 640 C.

                    Total burn time was around 10 minutes, and stopped with DPF status at 4%.



                    The app is glitchy (often loses the data flow/freezes, then either comes good again or I get out then get back in again). It can also log data to review later, but I haven’t played with that. It can also clear error codes.

                    So overall I was stoked – for $20 I had a new toy that enables me to check the DPF status (and other bits and stuff that is happening) and initiate a burn (assuming I can work out how to do it again) and clear codes if the DPF karkes it in the bush.

                    I’m keen to hear anyone’s experience if they go down the same route, or other IPhone apps that people recommend. Hope this helps!
                    Attached Files
                    Last edited by LeadWings; 12-01-2018, 02:25 PM.

                    Comment


                    • #40
                      Well done, pleased that you got it working. Could you tell me if your app gives the pid that it uses for DPF pressure please. There is a default dpf pressure gauge in torque pro which does not make any sense. It does sound as though torque pro and your app use the same pids if you managed to get the % working by using the same information (2138 j*2)

                      Comment


                      • #41
                        John, I had a look but unfortunately it won’t show me the factory PIDs

                        Comment


                        • #42
                          Post deleted
                          Last edited by JohnLynn; 06-02-2018, 04:35 PM.

                          Comment


                          • #43
                            Post deleted
                            Last edited by JohnLynn; 06-02-2018, 04:34 PM.

                            Comment


                            • #44
                              Post deleted as not required now that the PM system is working again
                              Last edited by JohnLynn; 06-02-2018, 04:34 PM.

                              Comment


                              • #45
                                Originally posted by ExNissan View Post
                                Hi All,
                                been following this forum since I picked up a shiny new 2016 GX 2.8 Auto mid last year and after a year of benefitting from the collective wisdom here I've got something to contribute back.

                                *USE THE FOLLOWING INFORMATION AT YOUR OWN RISK (impolite yelling intended)

                                A manual DPF regen can be triggered on the Prado/Fortuner 2.8L by issueing the following CAN message at the OBD port 07E0 05 30 29 06 01 01 00 00
                                It also happens to work as an OBD2 broadcast message which allows us to send it via OBD2 devices such as the scangauge/elm dongle and apps such as Torque Pro that dont appear to support messages for specific ID's.

                                In the android Torque application a custom button can be created for this command containg the raw OBD command data 30 29 06 01 01
                                In the Scangauge a custom command/message can be added containing 3029060101 as tested by my good mate dave-c over on the www.fortunerforum.com.au forums.

                                The motor needs to be running and ideally at operating temperature prior to sending this command (just once). The idle speed will come up to around 2000RPM and the engine ecu will run a full burn (dealer style?) for 10-15 minutes. The fast idle appears to be to bring the DPF core up to burn temperature and will taper off over time. Once complete the engine idle will return to normal. The burn can be stopped at any time by stopping the motor and will not resume at next start.

                                This has been tested on precisely one Prado (my 2016 2.8 Auto GX - without the DPF ECU update) and precisely one Fortuner (Dave's 2016 2.8L Auto - with the ECU update). This is why I yelled at the start of this post that using this is done at your own risk.

                                I had two reasons for wanting this ability:

                                1. I wanted to be able to force a dealer style regen if I'm stuck in the middle of the bush with a clogged DPF, a Prado in limp home mode and a pissed off missus.
                                2. I was hoping to be able to control when DPF burns take place so as to avoid the "burning the Prado to the ground" scenario, which for example could happen in spinifex midway along the CSR, by instead doing a manual regen at a time and place of my choosing. Say on a nice patch of bare dirt at every second or so campsite. DONE :-)

                                EDIT:
                                After further testing we know a bit more. The automatic regen burns are triggered at 100% DPF load (as noted by others) and as displayed by the scangauge/torque Pro and are only related to the magic 300km number by coincidence. Playing in Bendethra last weekend, and after an automated burn completed just prior to leaving the tar, I had the DPF back to 80+% in just over 100km of playing. Did a manual burn at the park exit (back to 8%) and then drove as per normal the rest of the week. The next automated burn kicked in at 100% which was 440 from the last automated burn and 340 or so from the manual burn.

                                So:
                                1. The burns trigger at 100% not a km value (as noted by others on the forums)
                                2. ~300km of easy/mid load driving does equate to around 100% dpf load
                                3. Playing off road can fill the DPF in 100km or less - Towing into a headwind too maybe???
                                4. The manual regen does postpone the automated burn as we expected/hoped so we can mitigate the fire risk offroad by burning when WE choose!. Though I dont know why my first test of this didnt work as expected.

                                Question - now that we have a way to monitor the DPF% has anyone seen it get hot enough to do a passive regen whilst driving? I havent done a long stint at 110 (cough) since Dave and I cracked the % PID but to date I have not seen the DPF light up or decrease by itself - only in response to the 5th injector firing.

                                We're also hoping to being able to read the dpf clogged % and display that on the scangauge/torque app. The info is there (I've seen it) we're just not sure how easy it will be to get it out, decoded and displayed. DONE :-)

                                Apologies if this info has allready been covered.

                                Cheers
                                -R
                                Thanks for your information. I want to try it as well. But, could you please recommend a OBD2 for me please? Cheers!

                                Comment

                                Working...
                                X