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linked
27-03-2011, 01:10 PM
Hi Guys,

I have recently removed my DPF and blanked the EGR valve ( all via "chip it" products), and the vehicle feels much better with more power and overall responsiveness. :biggrin:
I have been noticing that the ECU still triggers the auto re-gen DPF cleaning cycle every 100-300km, even though the original DPF is no longer there.
Is there anyway to remove this feature either via a sensor or ECU Mod? , as it is only just wasting gas and creating a lot of white smoke when it happens.

Thanks.

Old.Tony
27-03-2011, 09:22 PM
What we'd need to do is convince ChipIt to add some hardware (if it's not already there) and add one line of code in their chip.

It needs a crank angle sensor attachment (that's the extra hardware) and the code is:

IF (cylinder being asked to inject now) is not on its power stroke THEN ignore injector open request.

It's that easy. It would save buckets and the ECU wouldn't know it was happening.

Bosshog
27-03-2011, 10:30 PM
So much to say but I'll bite my tongue!

I'll call Justin at Chip It

the_bluester
28-03-2011, 12:12 AM
Should be nice and easy in a D40 V6 TDI, I believe they run a seventh injector for the DPF regen instead of cracking the main ones open during the exhaust stroke, assuming it does not throw codes or go into limp home, disconnect the injector and there you go, no more regen.

Old.Tony
28-03-2011, 01:36 AM
So much to say but I'll bite my tongue!

I'll call Justin at Chip It

We had a bit of discussion about this, and I'm sure it's the right direction given everything else that we know about the system.

Should be nice and easy in a D40 V6 TDI, I believe they run a seventh injector for the DPF regen instead of cracking the main ones open during the exhaust stroke, assuming it does not throw codes or go into limp home, disconnect the injector and there you go, no more regen.

I bet it sends it into limp mode almost immediately.

The regen cycle apparently happens every 100-300km. If it's that frequent, then the system MUST be designed to ensure that it will be able to do a regen that frequently and will have safeguards built in so that if it detects there's a possible failure that will prevent it from doing it, it renders the vehicle unusable.

I'm not sure the injectors report the presence of fuel or the rate/pressure that fuel was delivered when opened. If the injector's fuel line is removed you'd achieve your goal and probably won't trigger any codes in the ECU. To hell with the injector, let it click away for all its worth!

The only thing that would stop this working is if they are using the O2 sensors to monitor it. As you inject more fuel into the exhaust, the O2 sensor in front of the DPF would still register oxygen but the one behind the DPF (further from the engine) would not, as the oxygen is consumed by the combustion of the fuel on the DPF itself.

Similar to the way the O2 sensors themselves are detected, all they have to do is vary the output of the 7th injector by a small amount and watch for that variance to be reflected in the second O2 sensor. If there are no changes in the second O2 sensor based on an injector open/close command, the ECU would rightly deduce that there's a problem with that injector and fire off a problem code, possibly resorting to limp mode if it isn't fixed within a certain time.

If I was an asshole programmer working for Nissan, that's what I'd do.

Leprechaun
28-03-2011, 02:03 AM
What we'd need to do is convince ChipIt to add some hardware (if it's not already there) and add one line of code in their chip.

It needs a crank angle sensor attachment (that's the extra hardware) and the code is:

IF (cylinder being asked to inject now) is not on its power stroke THEN ignore injector open request.

It's that easy. It would save buckets and the ECU wouldn't know it was happening.

I don't think the Chipit is that clever, it simply adjusts boost and fuel rail pressures. No plugs or wiring to the injectors.

Bosshog
28-03-2011, 03:11 AM
I don't think the Chipit is that clever, it simply adjusts boost and fuel rail pressures. No plugs or wiring to the injectors.

Correct! What I am going to ask them to do is make a chip that can monitor the crank angle and stop the injector putting fuel in on the exhaust stroke. I can only ask.

the_bluester
28-03-2011, 03:46 AM
That or as an "Interceptor" type chip it may be able to intercept and modify the inputs to the ECU that monitor the DPF condition and feed the ECU inputs that look as though the DPF is not in need of a regen.

robbos40
28-03-2011, 10:01 AM
What about tapping the dpf injector into the supply fuel line or the tank filler? It would still fire the injector but would return to the fuel supply and not get waisted up in white smoke.

Old.Tony
28-03-2011, 09:12 PM
I wouldn't want to hold one of those injectors near rubber. It might produce a fine mist, but it's under extremely high pressure - higher if the car's been chipped - and rubber would deteriorate rapidly. That doesn't mean you can't make up a metal enclosure with some stainless steel and mount the injector in that and achieve what you want!

linked
28-03-2011, 09:49 PM
Wow, really good information so far!
I agree the chip option should be possible as this company (DPF-R "THE" DPF DELETE (http://dpf-r.gearboxz.com/)) as created a chip for Ford Trucks that does something quite similar.

I have also researched the option of remapping the ECU directly, and have come across this software solution (ECUsafe home (http://ecusafe.com)), which seems to have the ability to remove the DPF function along with other parameters like the speed limiter removal.

I am assuming you would access the ECU via the cars On-Board Diagnostics port, anyone out there familiar with this process?

westy350
29-03-2011, 04:11 AM
Boss hog you still got smoke problems? let us know how you go with Chip it i'm going up to see Justin in a couple of weeks.

Rickstar
29-03-2011, 04:53 AM
I had no problems with white smoke when I had to stock exhaust with the dpf removed and all sensors fitted to a replacement pipe.Steinbauer chip and all. My problems started when I went 3" stainless inc dump all the way.I have a 3" cat installed in the system and a muffler.Not long after I had the dreaded white smoke.I made up an O2 sensor extension about 20mm and no problems.Done about 10000 k,s.Might have been Bosshogs idea.

Rich64
17-04-2011, 12:24 PM
Hi Guys,

I have recently removed my DPF and blanked the EGR valve ( all via "chip it" products), and the vehicle feels much better with more power and overall responsiveness. :biggrin:
I have been noticing that the ECU still triggers the auto re-gen DPF cleaning cycle every 100-300km, even though the original DPF is no longer there.
Is there anyway to remove this feature either via a sensor or ECU Mod? , as it is only just wasting gas and creating a lot of white smoke when it happens.

Thanks.

My understanding is that the "burn" should not occur any longer once the DPF is removed, as there should be no readings from the sensors to trigger it..

Bosshog
18-04-2011, 06:10 AM
Boss hog you still got smoke problems? let us know how you go with Chip it i'm going up to see Justin in a couple of weeks.

I had no problems with white smoke when I had to stock exhaust with the dpf removed and all sensors fitted to a replacement pipe.Steinbauer chip and all. My problems started when I went 3" stainless inc dump all the way.I have a 3" cat installed in the system and a muffler.Not long after I had the dreaded white smoke.I made up an O2 sensor extension about 20mm and no problems.Done about 10000 k,s.Might have been Bosshogs idea.

Stepping out the O2 sensors works, but in my case the hole I drilled blocked up and this has triggered a burn. Just need a bigger hole for the gases to reach the sensor.

As Rickstar says removing the factory cat is when the issues start.

Old.Tony
18-04-2011, 11:39 AM
Stepping out the O2 sensors works, but in my case the hole I drilled blocked up and this has triggered a burn. Just need a bigger hole for the gases to reach the sensor.

As Rickstar says removing the factory cat is when the issues start.

Ok, so what sensor is in the CAT to cause this? Why not just position that sensor in the pipe that replaces the CAT ?

The manual shows something at the front of the CAT that may take a sensor but I haven't spent a lot of time searching for what that might be.

DieselTuner2
18-04-2011, 11:49 AM
Alot of exhaust shops that put high performance cats in systems dont actually realise that a petrol cat, and a diesel cat are two different animals.

Petrol cat wont work at all in a diesel...
Diesel cat will melt in a petrol in no time...