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Dooper Hesitant & Smokey

4K views 32 replies 5 participants last post by  SeanC 
#1 ·
Evening All,

2008 Mini Cooper Diesel (94,000 miles).

Symptoms:
- Engine 'misfires'/hesitates at low revs (less than 1500 rpm), usually when taking off from junctions etc...
- Slight smell of exhaust fumes coming from the vents

What I've done so far;
- Full service (all filters renewed)
- Replaced orange turbo seal (Cracked)
- Replaced Charge Air Tube (There was a small split in the rubber hose)
- Replaced EGR valve (secondhand unit from eBay)
- Cleaned fuel system with Redex

Still the same! Been chasing this one for a long time now, really starting to annoy me!

Anybody else out there shed any light on this one?

Any comments appreciated.
 
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#4 ·
Engine possibly a bit noisier - hard to say... What you thinking?
At this moment I'm thinking Turbo or injectors. Lets look at the turbo first, have you checked it for end float and checked the actuator? I'm asking this because you have already said that you have changed the turbo seal. I presume it got perished due to oil and if too much oil is passing through the turbo then that's not a good sign.

Have you had a diagnostic check done on the car to see if any sensors have been triggered? A misfire usually logs a fault.
 
#6 ·
Forget the glow plug error buddy as that aint your fault. Check the turbo for end float so pop the intake pipe off and feel the propeller as per photo. If it wiggles too much then that may very well be your problem!



Also check the condition of the actuator!
 
#9 ·
Also check the gasket on the exhaust side of the Turbo, its a big ring held under a clamp. The easiest way to see if its been leaking is to check the underside of the bonnet for any tell tail exhaust soot stains, failing that try and rub your finger under the heatshield of the turbo and if your finger comes out black then your Turbo is leaking, if you can remove the top of the heatshield for a better look then thats even better (3 10mm bolts from memory)

Pic of turbo, to the left where the turbo meets the DPF filter is where it will be leaking exhaust fumes so this is where you want to be looking. The gasket is under the clamp and mates between the DPF and Turbo exhaust/ wastegate

 
#10 ·
Evening,
OK - Had another look....Pics attached.

Minor, and I mean minor, forward and aft float on the turbo... should it be 'rock solid'?
The Actuator is functioning (see it moving up and down).

The is soot around the turbo as seen in the photos.

ANOTHER NOTE - I noticed this evening that the seat around one of the injectors does appear wet with oil (other 3 appear to be 'bone dry')??? This could be the cause of the exhaust fumes in the cabin???? Surely not the hesitation???
 

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#11 ·
The soot on the turbo will need investigated further but lets put that on the back burner for the moment and the movement you describe is fine so lets turn to the wet injector as this was going going to be my next line of investigation. The wet injector is diesel passing through and will omit fumes which is possibly what you will be smelling in the cabin. You will need new injector seals and the good news is that the fix isn't expensive, the bad news is the injector may be an absolute arse to remove if they are tight but a soak in some wd40 usually slackens them up
 
#16 ·
I don't think your being paranoid buddy, when your accelerating your putting more fuel into the engine and if some fuel is escaping which it is in your case then the car will hesitate and gasses will escape too - hence the smell of fumes! Try and not to drive it if possible until you have the leaky injector fixed ::wink::
 
#18 ·
OK Guys, small update....

I ordered new copper seals off eBay, but they have not arrived yet!!!! :(

I had a bit of time this morning, so I decided to pull out injector #4 (the leaky one) and have a look.... Attached images of what I found!!!!:eeksurprise:

Looks like I need a FULL INJECTOR SEAL kit, not just the copper washers! Probably best to do all 4 when I'm at it! Any ideas on how to clean the seat of the copper washer, down in the block??

What do you think?
 

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#19 ·
Funny how its always injector 4 as my dooper had to have this injector replaced as it broke while being removed due to leaking by the previous owner. To clean it out I'd use brake cleaner as this will dissolve the oil/ diesel and remove any contaminants. Block up the hole first!
 
#21 ·
UPDATE

Replaced all injector seals (not just the copper washers).
One injector was completely soaked with oil!

Still got the exhaust smell in the cabin!! Haven't noticed the hesitation, but will need a longer drive. Tomorrow's commute will be a better test.
 

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#23 ·
Good to see that your making progress. Re the exhaust smell you will need to turn your attention to that soot on the turbo so get the top shroud off the heat shield and see what the underside of the heat shield is like and the joints between the turbo and the DPF/ manifold etc
 
#27 ·
Plan to get the heat shield off tomorrow and have a look at the exhaust seals as you suggest. I've also got a new rocker cover gasket and will replace that tomorrow as well - maybe that was the cause of the injector being soaked with oil.

I'll post some more pics and an update tomorrow, all being well.

Thanks!!
 
#29 ·
OK - Think I've found the source for the smoke getting into the cabin! The clamp on the EGR valve was loose!! Noticed when putting the air box back on, there was soot build up on the outside.... "Wonder where that's coming from...?" moment. Checked the EGR clamp and hey presto - loose! Tightened it up and this seems to have eliminated the smell coming through the vents!!
 

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