DPF problem with lack of acceleration

Ambulance2Camper

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To all the hive mind. I have a merc sprinter w906 2.2 ,150BHP. I have had issues with my DPF not doing any regens , even forced ones didnt clear it. I have had 3 DPF’s in 6 years. After about 5,000 miles it starts smoking and the warning light comes on and enters limp mode. I’m usually away on holiday and i nurse the vehicle home. I tried physically cleaning the DPF with fluids and foam blowing out the back but nothing worked. The latest episode happened whilst in Paris at the olympics last summer. I nursed it home and fitted another new DPF. I got a friend to modify my ECU with “new DPF’. Ongoing i wasn’t happy with it smoking so much and although i had no engine light on i felt it was going wrong again. It was definitely not pulling and accelerating as fast as it should. It felt like half limp mode. So this time i hollowed it out and took my ecu to a garage for a DPF delete.
It’s all fitted back in and i took it for a test drive. It’s got the same issues as i recently experienced with slow acceleration and no real power. It’s as if the turbo is not working. It’s the twin turbo 2.2 engine. Could it be the turbo has failed from ‘back pressure’? There’s no leaks of oil around it. I can’t hear it whizz up when throttling. How do i check this? Nothing has shown up on my icarsoft reader. I don’t know what to do/ check next. Any help greatly appreciated. Thanks .

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loss of power could also be a leak in one of the best pipes. Do you have a code reader as this will narrow it down for you. look for oily residue around the rubber boost hoses. When mine went though it was at the back of the pipe so couldn't see anything until I removed it
 
Generally speaking the three rules of a diesel exhaust are:
1) If the smoke is white the diesel is being injected but not burnt
2) If the smoke is dense black the diesel is being burnt but the mixture is rich.
3) If the engine will not run, there is no diesel being injected
My guess would be that the fuel pump / or injectors are injecting too much fuel or the injector pump timing is out. I would suspect the injectors to be at fault. If the DPF is full, the exhaust has nowhere to go so it is not leaving the combustion chamber, thus cutting the engine power.
 
Generally speaking the three rules of a diesel exhaust are:
1) If the smoke is white the diesel is being injected but not burnt
2) If the smoke is dense black the diesel is being burnt but the mixture is rich.
3) If the engine will not run, there is no diesel being injected
My guess would be that the fuel pump / or injectors are injecting too much fuel or the injector pump timing is out. I would suspect the injectors to be at fault. If the DPF is full, the exhaust has nowhere to go so it is not leaving the combustion chamber, thus cutting the engine power.
OR an air leak on high pressure side
 
OR an air leak on high pressure side
I know not all there is to know about turbos I must admit, but what you say seems quite logical. If there is an air leak on the high pressure side of the turbo, logically less air is pumped into the chamber thus the mixture is rich.
Got it.
I think. Thank you for adding to my diesel knowledge nabsim.
I fell in love with diesels in 1968 when a friend who was a vehicle mechanic with the Post Office bought an old (1956) London Taxi. The FX3, the one without a front passenger door. A gang of us piled into it and we went off for a weeks camping on the Isle of Wight. On the way there the taxi started smelling of diesel fuel. We all piled out and while the others went of in search of ice creams, my mate the mechanic opened the bonnet and explained to me how it all works. I was enchanted, I loved the smell of diesel, and thought it was quite wonderful how it burns under compression without any spark needed. He tightened a pipe nut, all was well and we had a lovely holiday. Imagine a gang of youths, with gorgeous 1960's teenage girls, all sun bathing on Sandown beach scoffing Ice Cream Melbas. Perhaps for the sake of explanation the girls had separate tents from the boys. We were a church youth group and didn't do whatever teenage girls and boys did in the 1960's.
Remembering that FX3, it needed some steering track rod end ball joints. My friend the mechanic took them into the PO workshop, filled out the worn bits with braze, filed them down roughly circular and then replaced them. It then passed the MOT. Years later, I bought it off him. I took it for an MOT and the tester scratched his chin, sucked air in through his teeth and said well, I dunno. In an emergency stop I don't know if the body would stay attached to the chassis. I replied 'this thing is not capable of an emergency stop so that won't be a problem.' He said 'yes, you're right. That's a pass then'.
 
I had a very similar intermittent power loss issue with my diesel car which then became a permanent problem. It turned out that the turbo was so carboned up that it could not turn at all. With a new turbo core and a DPF delete it runs great now.
 
I was expecting someone to suggest a (partially) blocked catalytic converter..... is there a reason why this hasn't been considered?
 
To all the hive mind. I have a merc sprinter w906 2.2 ,150BHP. I have had issues with my DPF not doing any regens , even forced ones didnt clear it. I have had 3 DPF’s in 6 years. After about 5,000 miles it starts smoking and the warning light comes on and enters limp mode. I’m usually away on holiday and i nurse the vehicle home. I tried physically cleaning the DPF with fluids and foam blowing out the back but nothing worked. The latest episode happened whilst in Paris at the olympics last summer. I nursed it home and fitted another new DPF. I got a friend to modify my ECU with “new DPF’. Ongoing i wasn’t happy with it smoking so much and although i had no engine light on i felt it was going wrong again. It was definitely not pulling and accelerating as fast as it should. It felt like half limp mode. So this time i hollowed it out and took my ecu to a garage for a DPF delete.
It’s all fitted back in and i took it for a test drive. It’s got the same issues as i recently experienced with slow acceleration and no real power. It’s as if the turbo is not working. It’s the twin turbo 2.2 engine. Could it be the turbo has failed from ‘back pressure’? There’s no leaks of oil around it. I can’t hear it whizz up when throttling. How do i check this? Nothing has shown up on my icarsoft reader. I don’t know what to do/ check next. Any help greatly appreciated. Thanks .
Min Sprinter did the same. And I had to change the second sensor down at the bottom end of the Filter. Reset the code and ok from then, it showed up because I tried force regen but it would not sense the balance between the two end sensors
 
hi dont know how much you can do your self dpf check undo exhaust clamp in front of dpf let it blow give it a
run. power ok ok dpf blooked check turbo take inlet pipe off air one (not exhaust side) check for lots of oil pipe full of oil seal worn get hold of spindle if it lifts a lot turbo worn if not get an expert to tell you what it is
 
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