Suspected misfire on WOT!

[Ironboer]

I'm so glad to see that this issue has been brought up on the forum. Bought my mini 2 weeks ago from Mini dealer and 2 days ago noticed the same misfire in 3rd gear between 4000rpm and 5000rpm.
I find it hard to believe what Raul is saying about carbon build-up. Carbon build-up occurs when your air/fuel mixture is not right. Cars with computerised fuel management systems are very acurate with the mixture levels in order to keep CO emmitions down. I'm tempted to follow Raul's advice but surely the Mini dealer should have seen this before handing the car over to me. I'm taking my mini back this monday to the dealer so they can sort their sh*t out. I recon it could be a fault on the engin management system when the overboost has to kick in between 4 and 5000rpm.

[Ironboer]

On Monday was driving the car and suddenly started misfiring badly. Even when Idling. Sounded like the car was just running on 3 pistons which I think it did. And on the motorway the car was unable to reach above 70mph, engine warning light came on as soon as the revs went above 3000rpm. Was not impress with the mini dealer at all! Took The car in today and made them understand that I was not impress at all with them for selling me a car that was not thoroughly checked. So much for BMW's 7 point check before selling. This afternoon the car was fixed already. They probably realised that they would have to pull up their socks. Car is running superb now and according to them it was a Spark plug failure. The service indicator is showing that I still have 4000miles to go before next service. That I dont understand.

[kroolio]

Hi

Im new here, only had the car since the begging of Jan.

Anyway, I have seemingly got the same problem you are all experiencing, my car has 30,000 miles on a 56 plate (I have a years warranty that covers everything - only problem is it is from the JCT600 group whos mini dealerships are based up north and im in Watford.

Anyway, when overboost kicks in, 4th gear seems to misfire and it sounds like a quick popping sound coming from the exhaust behind you. Is this the same thing you are all experiencing. I had the peugeout GT prior to my S and that car never suffered from this, however did suffer from a whole host of other problems that peugeot never managed to fix, Cam chain tensioner being one of them (that said, wasnt too fussed, company leased car and they were having it back after a year!).

This car is mine however and is obviously a concern.



Please help me shed some light on what to do next.

Thanks

Craig

[Jimbo1989]

Hi again everyone, i had this problem fixed after the garage having the car for just over a month! The car had been in 6 times before for the same problem but they kept saying there was nothing wrong with it. On the 5th time they changed a spark plug and then said it was fine, so i went to pick it up and turned around 20 metres down the road as it was still doing it and they didnt believe me until i took them out in it! was very satisfying seeing the service guys face when i had proved him wrong and that the car still had a problem!! They then couldnt work out what was wrong with it, they changed cylinders, pistons and a whole load of other (i lost track of what they were chaning in the end) that had been broken because of the original problem that THEY didnt spot in the first place. In the end they changed a high pressure oil pump ( i think!) and that seemed to do the job. Very irritating experiance but car seems to be fine now thank god!

[Union Jacks]

Quote: Originally Posted by Ironboer (original)

I'm so glad to see that this issue has been brought up on the forum. Bought my mini 2 weeks ago from Mini dealer and 2 days ago noticed the same misfire in 3rd gear between 4000rpm and 5000rpm.
I find it hard to believe what Raul is saying about carbon build-up. Carbon build-up occurs when your air/fuel mixture is not right. Cars with computerised fuel management systems are very acurate with the mixture levels in order to keep CO emmitions down. I'm tempted to follow Raul's advice but surely the Mini dealer should have seen this before handing the car over to me. I'm taking my mini back this monday to the dealer so they can sort their sh*t out. I recon it could be a fault on the engin management system when the overboost has to kick in between 4 and 5000rpm.

Hey all,
Had my R56 decoked at 23K miles due to misfire at low revs and during idle - dealer said due to driving technique (i'm using it as a learner car) and substandrad fuel from Tesco's.

Now 50K miles later and after a new engine due to excessive oil use; its started again and is at the momemt in Rybrook MINI waiting to be decoked again.

I'D LIKE TO HEAR FROM ANYONE ELSE WHO HAS FINALLY BEEN TOLD THAT THE MISSFIRE IS DUE TO CARBON BUILD UP PLEASE!!!!!!

[kroolio]

Union Jacks, can I ask what they classifed as excessive oil use as mine is using over a litre every 500 miles which I think is ridiculous!! They tell me this is normal!!

Its in the garage with Mini at the moment and they tell me my misfire on WOT and full boost is beacause of two coils needing replacing which they are replacing. (I am sceptical!!).

[Robot Features]

Hey guys

Got mine back late last week. Surprisingly it is now fixed. Nothing to do with carbon build up or anything mentioned above. Simply a loose hose to the intercooler and induction. My car drives better than before. The turbo is more evident now. Definitely no more misfiring. As for the oil consumption, they said the same thing to me also. They reckon 1 litre per 4000kms.

[Union Jacks]

Quote: Originally Posted by kroolio (original)

Union Jacks, can I ask what they classifed as excessive oil use as mine is using over a litre every 500 miles which I think is ridiculous!! They tell me this is normal!!

Its in the garage with Mini at the moment and they tell me my misfire on WOT and full boost is beacause of two coils needing replacing which they are replacing. (I am sceptical!!).

Hi there is a certain ammount the MINI is allowed to use - if it goes over this ammount then during Warranty the excessive oil use must be fixed - my friend had his stripped and the valve seals were replaced.

My engine was replaced after the strip down didn't stop the oil consumption.

Ring any MINI Dealer - they will tell you the maximum allowed oil use - i think its mentioned by me in this forum somewhere.

[raycbutler]

Im also experiancing a missfire and a couple of loud clicks followed by smoke out the back (2007 cooper s) generally happens when my foot goes down heading onto motorways etc, had it into mini and they said they saw a fault but cleared it... without taking note of what the fault was (helpful!) the car is also using about a liter of oil a month.. slightly concerned...

on the bright side it hasnt sounded like a bag of bolts on idle this month

[Robot Features]

Hi raycbutler

i'm experiencing the EXACT same issues as yours. As per my post above, i thought the loose hose was the problem. It wasnt. If anything the work they did made it worse. They then cleaned all the carbon in the valves and changed the high pressure fuel pump. Got the car back weeks ago and is driving great. The million dollar question though.. has it fixed the problem... NOT AT ALL. still getting the missfire with loud clicks and the puff of black smoke at the back. Also chewing a heap of oil.

Final resolution for me... I GIVE UP. Getting rid of my car soon enough. Decided not too stress about it and just accept it.

I will write a formal complaint to BMW once i rid of the car.

Mic

[raycbutler]

difficult.. i have also considered a trade in but appart from the engine idle sounding like a bag of bolts on occasions, being a thirsty oil bucket and mis fires... its a great car... shame mini dont seem to have a clue how to resolve these issues.

[Robot Features]

so true. its a real shame.