Sprinter 311 smoking please help

[andy parky]

Let me start by saying hi , first post on here ,

I recently bought 2008 sprinter 311 lwb 123.000 miles , seemed to be well cared for , first 800 all is well ...
until , the smoke started !! White smoke pouring from the exhaust..

So ... I had a mechanic call out to try and diagnose the fault .. no codes detected ..
DPF checked all clear reading 0%
MAP sensor changed
MAF sensor changed
EGR valve changed
TURBO changed and actuator
But runs great , ticks over fine , DOESNT USE OIL OR COOLANT

It doesn’t smoke when driving , only at idle , As I am driving along I hear the engine tone change , as if the exhaust is blowing , look I’m the mirror and it’s white smoke pouring out , I turn the key on and off , no ore smoke for a few more miles , no power loss or EML on
I am at my wits end with it now , where do I go next ‍

Any info would be very appreciated

 

[vincentfishing]

I would do a leak off test to check condition of injectors , white smoke is generally overfueling, could be sticking needle or control valve in injector sticking/overfuelling intermittently, a leak off test will give you an idea of the injector condition and may show one particularly bad one , only takes a couple of minutes and is easy to do diy

 

[andy parky]

I would do a leak off test to check condition of injectors , white smoke is generally overfueling, could be sticking needle or control valve in injector sticking/overfuelling intermittently, a leak off test will give you an idea of the injector condition and may show one particularly bad one , only takes a couple of minutes and is easy to do diy

i will give it a go tomorrow and keep you posted on the outcome , thanks for the reply

 

[vincentfishing]

i will give it a go tomorrow and keep you posted on the outcome , thanks for the reply

remember to clamp off leak off return pipe where it leaves last injector and heads off across engine, I just clamp it with mole grips, saves getting lots of air in fuel system

 

[oigle]

A crook injector shouldn't vary like that. Either bad or not really. With the "change of engine sound" etc you mentioned, would it be possible that the egr is doing a regen? When traveling, the exhaust would be much less likely to be seen with air speed around the exhaust. When stopped, the regen would continue and be very obvious with exhaust smoke. White seems a bit funny tho'. I would have thought it would be a darker colour.

 

[andy parky]

A crook injector shouldn't vary like that. Either bad or not really. With the "change of engine sound" etc you mentioned, would it be possible that the egr is doing a regen? When traveling, the exhaust would be much less likely to be seen with air speed around the exhaust. When stopped, the regen would continue and be very obvious with exhaust smoke. White seems a bit funny tho'. I would have thought it would be a darker colour.

I had a bloke come out with his snap on diagnostic, he tried to Make it run a regen , it reved up for 2 or 3 mins then kicked him out the program , saying 0% in the filter , so was not possible to run it threw its cycle

 

[andy parky]

It’s likes something is re setting itself when I turn the key on and off , it goes back to normal for a few miles , then the sound starts and so does the smoke

I have noticed this morning when it’s at it’s worse (smoking) I rev to 3000rpm and it’s ruff , as if it’s missing ...
turn the key on and off do the same test and at 3000 rpm a smooth tone from the engine running fine with no smoke

 

[vincentfishing]

It doesn’t smoke when driving , only at idle , As I am driving along I hear the engine tone change , as if the exhaust is blowing , look I’m the mirror and it’s white smoke pouring out

confused
it doesn't smoke when driving only at idle
then you say when driving ,engine note changed and white smoke pouring out.
last time I had this it was nozzle/drip ,
luckily I had a 5cylinder and blocked off fuel supply to dodgy injector , problem stopped,(drove on 4 cylinders till injector changed)
however I didn't have dpf system to worry about and one of the reasons I avoid dpf vehicles
good luck

 

[andy parky]

Sorry to confuse ,
Driving along I hear the engine tone change , i stop at a junction etc and smoke pouring out , drive off and it’s gone ,

I am about to do a leak test , I will post the results

 

[Kev555]

Strange one but with no fault codes and obvious things already replaced I would be looking at injectors next. like to see the source of this as bad injectors would show up under load more than often. How long has it been doing this?

 

[vincentfishing]

Does make me wonder why when a higher mileage motor starts to play up a quick leak off test , which costs next to nothing ,is so simple to do and if nothing else tells you what wear and tear you have on them is the first thing to do, before ecu's and sensors and modern cars, if some thing went wrong with your car (which in majority of cases would have been petrol) you would start by checking plugs, then leads then distributor contacts or cracks /coil/etc, common sense and fault finding has been taken over by 'computer says' not saying diagnostics isn't handy tool to have , but its not the be all and end all,
I broke down a long time ago and luckily a Scania truck was also broken down just up rd, a Scania service van from Europe had come to fix it, spoke to guy who I made the mistake of calling him a fitter, he abruptly said , in England you have fitters that replace parts ! we have mechanics ! he still had a look at my motor , told me what was wrong what part I needed and yes next day fitted part and was on my way.

 

[andy parky]

 

[andy parky]

Results ... 1 and 2 seem ok .. 3 filled up quick and 4 filled up very quick , it was running for 15seconds max

 

[vincentfishing]

Results ... 1 and 2 seem ok .. 3 filled up quick and 4 filled up very quick , it was running for 15seconds max

Ideally you need to run it for about a minute and with the plastic pipes into bottles so you can measure how many ml's are leaking off, what seems like a lot in 15sec in a small very narrow tube might not be excessive, you can get a good length of pipe from a pet shop (airline tube for fish tank) for a couple of pounds, and use any bottles to collect leak off

 

[vincentfishing]

 

[vincentfishing]

Hi, did you manage to do full leak off test and have you sorted problem ??

 

[andy parky]

Sorry for the late reply , I got 2 new injectors, 3and 4 was bad ... after changing 3rd with no problems, the 4th decided to strip the threads out the head ... at that point I had just enough of the van , parked it up and bought another ... Thanks for all your help

 

[Jozef Deneuter]

My Sprinter was wrong in the fitting of the exhaust pipe to the motor, just before the diesel particulate filter. With a lot of guessing and searching with a stick with a simple chicken plume I had to detect it after the MB technician didn't find anything on his diagnostic tool! Just after a few 100 km and later every 100 000 km the filter will burn the particles by injecting fuell into the filter. While normally on the highway the white smoke escapes visa the exhaust end, in my case of mal-assembled exhaust pipe before the filter itself, I had an enormous worrying white smoke from under the hood, waiting on a traffic road... Thank you Mercedes, for NOT mentioning this smoke production wherever on my vehicle.