My daughter brought in her 2009 Mini Cooper R56 to a European shop as it was throwing codes (misfires on a couple of cylinders). Was an easy fix (on appearance) by just changing ignition coils, Her car, she decided to bring it to the shop anyway.

1) Shop suggested that the oil be changed. Done.
2) While up on the hoist, they noticed some play on the rear wheels and suggested that wheel bearings be changed. Note that there were no audible signs of wear to the bearings, or anything else for that matter. Changed the wheel bearings.
3) Pay bill. Drive away.
4) Not 5 minutes into the drive home, misfires began, engine light goes on. Basically same condition as before.

Bring it back to shop immediately. Get a call a few days later. Metal in crankcase, rings might be shot, cylinders likely scored. The motor is a time bomb by their account.

Car has 134K kms

So, ignoring the wheel bearings, They changed the oil and no mention of metal in oil was mentioned at all. After shop completes second series of diagnostics, they detect metal in oil? Make no sense. The damage would have to have taken place in the 5 minutes or so after we took the car back, or, it was already damaged?

So, $1,500 of likely unnecessary repairs (she wouldn't have repaired to bearings if it was a write-off), or the ignition coils for that matter and she now owns a boat anchor?

Going to have a very honest conversation with the shop, however wanted to know if the group had any suggestions as to how we might tackle this with them. Or, ideas on the repairs themselves.

Car has 134,000 kms

 

Metal in the oil would have been noticed on the oil change. Not sure how that could have been missed.

 

I had a car with metal in the oil. Changed the oil, removed all the white metal shavings from the sump, drove it for another 60K miles. Funny thing was, it was very sweet and high revving. Guess it didn't really need all its main bearings.

At this stage, you still don't have a proper diagnosis. What is the REASON it's misfiring? Metal in the sump doesn't make it misfire. Possible scoring doesn't make it misfire. Those are all symptoms, not a cause. What is the CAUSE?

Low compression would be a cause. So would an ignition problem. At this stage I doubt the competence of your mechanic.

 

Metal in the oil is not a good sign for sure, but consider this. I installed a re-manufactured engine from ATK into a 2003 Mazda Tribute; the oil had high levels of contamination right out of the gate. At some point prior to the 15,000 mile mark on the new engine, the bank 1 timing chain tensioner failed; the slack in the timing chain was so bad you could hear it, engine timing on bank 1 slipped one tooth, and with all that slack, the timing chain to contacted the timing chain cover dumping a lot of metal particles into the oil.

ATK paid my shop to change the timing chain tensioner and damaged components associated with that failure, and we started to take oil samples around the 2000 mile mark until we saw reductions in wear metals. It took two short run oil changes to flush all the junk out see attached report. In your case, you don't know what type of metal is in the oil; a proper oil analysis will shed some light on what components inside the engine are wearing. Make sure you send a note along with your sample to explain the situation with the engine; the lab will need that information to aid their analysis.

https://www.blackstone-labs.com/test...dard-analysis/ Blackstone will mail you free sample kits; I suggest you request 2-3 sample kits; kits are free. Cost of the analysis is $30.00

Additionally, you need a proper misfire diagnosis by a competent repair facility, and I would recommend a compression check/leak-down test to verify cylinder health.

 

Exactly this ^^^
While it's sometimes a necessity to take it to a shop, the fact is they will never really take care of it like their own because it's just another car to them... It was only after it came back that somehow metal in the crankcase became a "diagnosis". How did they come to that point?

Did you physically see any of the metal that they found, or are you taking them for their word? I would ask them very specifically, what method of troubleshooting led them to look at the oil? Did they drain the oil again and pull the filter, or did they dig through the trash and look at the old filter?
With the exception of the few shops that actually give a crap, most are just out to make money. (Recommending wheel bearings when there was no apparent issue, etc.)

I'll tell you exactly how they missed the alleged metal on the oil on the first go-around... They weren't paying attention. Whoever changed the oil just dropped the drain plug and walked away while the pain drained. When they pulled the filter, they probably just chucked it instead of looking at it and seeing if there was any contamination. When I change my oil, I usually let some of it run through my fingers or I hold a lint free rag in the stream for a second or two looking for any obvious contaminants. I also inspect my filters, either by taking them apart (MINI) or cutting them open. 99% of shops don't do that because time is money. There is no vested interest because it's not their personal vehicle.

It's perfectly normal to see a very small bit of metal in oil, or a very slight shimmer when you drain it... especially on higher mileage cars. You're dealing with friction surfaces. Bearing surfaces wear... it happens. It's when you start to see larger slivers and flakes that you need to start being concerned.

Personally, I would start looking elsewhere for someone that can give you a solid diagnosis of your original issue and go from there. A compression/leakdown test will give you a pretty good indication of the motor's overall health, but basic trouble shooting would have me looking at the electrical side first and then moving forward..

Good luck

 

A non-tech person with a Euro car needs to find and nurture a relationship with a mechanic they can trust.
The wheel bearings were not related to your issue and are not typically a high failure item - a good mechanic would say "these are a little loose, but lets keep an eye on them"
This leads me to believe you were indeed churned. Thats a lot of money to fix something that ain't broke.

I wonder if you even got new coils. Be sure to give neg feedback on google to the shop in question.

Don't trust easily - always ask why and what if - get, or at least see your old parts.

 

Looks like the original poster is long gone.

 

Still here. Nothing new to update until now.
Brought it to a new mechanic, who performed a compression test and found all cylinders above 120 PSI. So far so good. We came to learn that there were old spark plugs which needed to be changed. This struck me as curious, as I had put OEM spark plugs less than a year ago. Mechanic sent us a picture and there was a BMW plug and a couple others we didn't recognize. Makes no sense. Not sure why the original mechanic said that the motor was shot, the current one certainly doesn't. He did mention that the oil cap was loose and wasn't fitting properly. This was a previous issue which we addressed by getting a new one.

In summary, it looks like after changing the spark plugs (again), performing the compression test, that all is in order. Still don't understand why previous guy said the motor was a write-off. Makes no sense.

 

~~>$$$<~~ They already got you for a set of wheel bearings that may or may not have needed to be replaced. Why not aim high and try to convince you that the motor is shot?

I'm happy to hear that you took it too another mechanic and those compression numbers look pretty good. As long they're fairly even across all 4 (within 5psi or so) you should be good to go. Most importantly, did the misfire codes and whatnot go away and stay away?

 

With the R55-R61 platform most of the misfires are caused by bad plugs or a bad coil(s). These coils are know to not last that long and the heat cycles beats them up.

 

Spoke to mechanic yesterday. Motor is fine. Compression is 150 for all cylinders. Runs fine until hits the highway, then misfires occur. Coils new, spark plugs new. So, it's an electrical gremlin(s). Mechanic said that wiring harness has been butchered by previous owner. Problem lies there he believes. Quite a roller-coaster ride so far.

 

Sounds like heat is affecting something. Could be other electronics than the coil packs, even ECU.

Also could be a problem in the fuel system, like clogged fuel filter, bad fuel pump, or even blocked fuel tank vent - something that leads to loss of fuel pressure after some time. Can the fuel pressure be monitored while driving?

I once had a fuel pressure guage connected to my Jaguar XJR, fastened to one of the wiper arms, so I could see it while driving. That's how I found that fuel pressure was dropping, but only on prolonged full throttle.

Is the misfire code always on one cylinder, or on random / multiple ones?

 

^^Will be having a chat with Mechanic today, or tomorrow and will report back.

 

This (heat). I looks like there is a crack in the aluminum block, which results in oil somehow making its way into the coolant reservoir. When it gets up the heat, I guess pressure is being released there which in turn results in misfires. So...we can have the "block" replaced, or get a used motor put in. The mechanic adjusted one of the valves that wasn't seated properly and replaced the timing chain while he was at it. This initially cured the misfire.

He said he wouldn't charge anything for that work and we could take the car away and only pay for his diagnostic work for $300. Again, it was only when it came up to heat that a crack in the block was detected and/or assumed as the cylinders all have good compression. To my mind, get the aluminum block repaired would be the best option as we have a brand new timing chain and the valve work has been done. Used motor comes with a 6 month warranty and I really would have no sense as to how long it could be expected to last.

Thoughts?