BMW M57 3.0d slight misfire?

[dddrrift]

The old trusty X5 has developed a bit of a miss under light throttle cruising in higher gears.

I have INPA so read the codes and all I had come up was a smooth running control fault. Checked the Injector mass readings and no 2 cylinder was way above the threshold. Replaced it with a good used injector and all is well, readings are fine and no more fault code, however, my slight misfire is still there.

Anyone any ideas what else it could be? EGR is still in operation too.

Thanks

 

[Dub_cub 89]

All your leak off pipes ok?
Did you reset the adaptation value for the DDE?

If all cylinders are now in spec during the smooth running test it’s likely just one of the injectors leaking compression past the wee copper washer, can sound quite like a misfire if it’s a minor leak

 

[dddrrift]

all leak off pipes are grand, I didn't reset the adaption, should I?

 

[Dub_cub 89]

You don’t have to, not unless you change more than 2 of the injectors iirc, tbh I’d be looking for one leaking, spray some water mixed with a bit of fairy liquid around where the injectors slot into the head and see if you can get any air bubbles forming, can be hard to find compression leaking past until it’s a decent sized leak though

 

[dddrrift]

tell me about it! il give it a go, everything was spotless going back in, cleaned the seat for the washer too, I guess it could be another one perhaps

 

[colin84]

tell me about it! il give it a go, everything was spotless going back in, cleaned the seat for the washer too, I guess it could be another one perhaps

Did you replace the copper washer or use the old one?

 

[dddrrift]

changed it for a new one

 

[colin84]

Check for leaks as said above, and check the condition of your vacuum pipes also.

 

[dddrrift]

yeah I read about the vacuum pipes being a possible cause, mine don't look great so may replace them to rule them out

 

[Boksic]

Check the wiring harness to the injectors.
Had the same bother and replaced an injector etc etc, and it turned out the rubber seal on the harness to the injector had swollen slightly causing a poorer connection and occasional misfire..

Was a pain in the bum

 

[Boksic]

Ps if that's the cause I'll be looking an f'ing superb luckspenny on that other car.. I've already the replacement rack bought..

 

[dddrrift]

i tried not to upset the harness when changing the injector so im hoping that isnt the issue, its real strange, its the smallest wee miss only under light throttle, maybe better with some live data just to see whats happening! Full rack bought? lol jeez your not messing around!! shes well worth it though! left that power cable for the dash cam in for you too, might be handy if you get one for it!

 

[dddrrift]

so a month on and I still have this issue, if anything its getting worse. there are no leaks around the injector that was replaced. I checked the mass adjustment again via INPA over the weekend and no 6 is now reading high, just not quite high enough to trigger the smooth running fault code to be stored. It was no 2 that was replaced previously due to being out of adjustment range.

I'm tempted to just change all 6 if it can be done for reasonable money. Or can these injectors be refurbished? Iv heard mixed reviews on how successful refurbishing is.

 

[dddrrift]

so i had a good look at this last night, tried disconnevting maf and i isolated the EGR, no difference. however, iv had a slow puncture for a while now and i blew it up again last night as it looked a bit soft, problem has gone. Could it be anything to do with tyre radius? seems strange but it seems to have worked lol

 

[vesopa]

Hello, I am interested to find out how did you solve the misfire issue.
I seem to be developing the same problem.
The car is e46 m57.

I will appreciate if you follow up with some information .

 

[dddrrift]

turned out to be my transfer case at fault. your e46 wont have one as its not 4 wheel drive

 

[vesopa]

Ok, thank you.

 

[Haiky]

I seem to be developing the same problem.

I have also a X5 2005 year.

What kind of fault did your transfer case have?

 

[dddrrift]

it needs rebuilt or replaced probably, new clutch pack, chain and bearings etc if your going in that far. none of that is cheap. mine isnt worth spending that sort of money on, it has over 200,000 miles on it. I just unplugged the transfer case motor and drove on in rear wheel drive. 2 years later still going well! good luck!

 

[Lyons]

I had my transfer case rebuilt for £750, with new clutch pack etc.

 

[Haiky]

So the case was unplugged and there was no shaking. So it seems, the transfare case bad. The workshop will call the specialist shop tomorrow and will know the price for rebuild.

 

[dddrrift]

yep, unplug the transfer case motor and take it a drive, 4x4 light will be illuminated on the dash but should drive fine if that is your problem. Usual cause of transfer case damage is mismatched tyres. I had a slow puncture for a while and that's what ruined mine, albeit it had done 150k at least at that point.