Thread: Getting rid of dpd on a Mu-X

Hi,
We have got a 2018 MU-X 3l diesel , that we got second hand with 67000km last year.
The car has now 85000 km , and we are noticing that it does more and more regenerations of the dpd.
Like one regeneration every 18 to 20 km on short trips. Or another exemple, south Auckland to Hamilton and it would do 3 or 4 regenerations.
We took the car to the local Isuzu dealer, they have done all kind of tests, swapping sensors, driving around, etc, we are still stuck with the same problem.
So I have heard that you could get the dpd remove entirely, ( getting a partial new exhaust line to replace the dpd section), get the computer tweeked so it ignores the now obsolete sensors, and get a retune for proper combustion. And get an emission certification after that.

So the questions are:
- is that modification all right on the vehicle and for the engine durability ?
- what are the implications for future WOF, fuel consumption, insurance and resale value?
-what are the chances of failing the emission test after all the tune up is done?
If you had to get it done, where would you go? ( we live in the waikato ).
Thanks.

Hv you run a bottle of injector cleaner thru the motor?? The fuel additive?

My 2017 mux at 110k was doing regeneration really often and the gauge seemed to be going up and down randomly, was intending to do a delete and tune but before I got around to it the battery died, with a new battery all the DPD issues went away. The other thing that it fixed was the radio volume was previously randomly varying. So it seems that battery voltage was dropping when the alternator wasn't charging. I'm still tempted to do a delete and tune as with slightly larger tyres than standard it won't hold od sixth in a mild head wind or slight uphill at 100km so a bit more torque should help

Originally Posted by tac a1

Hv you run a bottle of injector cleaner thru the motor?? The fuel additive?

I thought they were a bit of feel good gimmick. Anybody else with real experience using them?

@Kobra, we ll look into the battery , thanks.

Well, you could theoretically get it recerted - but most people just gut the DPF housing and shove it back in then delete the thing in the ECU. No one at the WOF level has the gear to test for this, and if it's identical externally how would they know?

I think that's what you mean - diesel particulate filter? Dunno, don't like guessing but not sure about a dpd and usually I guess and look dumb haha.

Usually - this is done hand in hand with deleting the EGR setup and blanking that off (exhaust gas reticulation) as both systems work together to reduce emissions and if you chuck one you don't need the other.

More of a concern for me is the WHY your dpf setup is behaving like that, if the dealer has swapped sensors and done all of that side of the checks (swap parts at random and hope to stumble over the right solution is the cynical answer). You really need to know what is going on as it could be something else triggering it that is a sign of a larger whoops. I can't think off the top of my head what would cause multiple regen cycles like that in terms of one failed sensor or a single part, but each time the engine does this it's effectively restricting air intake and boosting the amount of fuel injected to increase the exhaust gas temperatures. This is what starts the regen 'burn' which clears the soot out of the dpf unit and opens things up, so I'm wondering if you have an injector or injection system issue combined with a air intake problem to make the computer think it needs to do the regen. Running the engine like that isn't ideal as it increases the remperatures of the pistons and internals all the way through the turbo and out the back end, and eventually can cause things to start not being happy. Even the engine oil doesn't like this, and it can cause excessive sooting of the oil which means your oil filter and lubrication isn't working as it should.

DPD is what Isuzu called the dpf, diesel particulate diffuser

Originally Posted by Friwi

I thought they were a bit of feel good gimmick. Anybody else with real experience using them?

@Kobra, we ll look into the battery , thanks.

Yes. Wynns EDT is my go to - it's a biocide and solvent/cleaner with added lubricity stuff. I use it regularly with my ranger, as it had a dose of bug in the past which was uncovered as part of other investigative work (and unfortunately threw the mechs off the scent for what was actually the issue, also weird as I was only filling off commercial retail suppliers).

In the past I've had a rough running Hyundai Tucson, went through some investigation and mechs were saying pull injectors blah blah. A mate said what have you got to lose - try some mechanic in a bottle... I had the EDT through running it in the boat to keep the bug from getting into it so went what the hell? Had a nearly empty tank, chucked a tank full's worth of EDT 'treatment dose' in and went down the road to fill up. I didn't get 2Km down the road before the rough running was gone, replaced by silky smooth much quieter and more responsive diesel engine noises - no more knocking or farting about. Had the same thing on other engines too...

So yes, the additives can work and work well but in some cases they can also create an issue if there is a lot of crap in the system by loosening up debris and moving it into somewhere it shouldn't be. Also, if you have a mechanical issue and the problem isn't related to crap in the works the cleaners won't work and can make the problem worse by removing more stuff from worn injector and the like. It won't fix injector patterns if the injector nozzle is chewed out is another way of looking at it.

Originally Posted by Kobra

DPD is what Isuzu called the dpf, diesel particulate diffuser

Ahhh well whaddya know. I do know haha. Should have called it the DSST, diesel sooty shite trap...

before that i suggest you look inside the inlet manifold and see if its full of "tar"
if its not hugely clogged "royal egr cleaner " works but do it outside on a windy day

I've got a bt50 Mazda. It started that carry-on service check showed 150% soot loading? how you can get over 100 I don't know. They removed the unit scraped the shit out, it was clogged put it back. All was fine for 20k then back at it. This time the pulled it all apart and thought to also look at the little injector doohickey that squirts fuel on the unit to burn it clean. It was stuffed so got replaced and the unit reamed out again. It's been no trouble since.

Youll need to gut the dpf and weld it back together so it doesnt look tampered with. ( I think its actually illegal to tamper with it) then theres guys around that can remap your ecu. Be careful if you gut the dpf as I think the dust off it is pretty bad for you. We have had it done to a few vehicles but we are up in auk

Originally Posted by gonetropo

before that i suggest you look inside the inlet manifold and see if its full of "tar"
if its not hugely clogged "royal egr cleaner " works but do it outside on a windy day

Yep true this, the Ranger was only a thin layer on the manifold so got a prompt ignoring until next time...

Originally Posted by Friwi

I thought they were a bit of feel good gimmick. Anybody else with real experience using them?

@Kobra, we ll look into the battery , thanks.

The green fuel cleaner..sorry can't think of name,is definately good stuff.

Originally Posted by Micky Duck

The green fuel cleaner..sorry can't think of name,is definately good stuff.

https://www.supercheapauto.co.nz/p/f...070702#start=5

Hmmm... I like the idea of using one of those bottles, much easier than the EDT one. I think I have an empty one loafing out in the shed, must try it out!