M Coupe Spluttering exhaust??

agentbiscuit

Member
 Aberdeen
Hi all,

This happened for no apparent reason. Half way through a tank of fuel, I had driven the car about 10 miles to my sisters house not thrashing the car but being quite progressive.... car sat outside for about an hour. Then when I drove out of the drive, I noticed there was a shake through the steering wheel. I thought it was the power steering playing up but the car nearly stalled in 1st when I pulled away and the emissions light came on. It got progressively worse and the car sounds a bit like a burbly impreza. Also very much down in power.

I'll take it to my dealer and hopefully they will see it this week, but in the meantime, anyone know what it might be?

For the record, there is no evidence of leaks, no visible holes in the exhaust, air box looks okay.

On the upside, the car sounds amazing, lots of pops and bangs.
 
Have a look at the o2 sensors on the manifold. Mine popped out about a year ago.. in similar conditions ( not thrashing the car but being quite progressive.... :rofl: ). I called BMW and they sent one of their techies round, as soon as he started the car, he new what the problem was.

My suggestion is start the engine, open the bonnet see if any of the sensors has come loose or off completely - alternatively the exhaust system may have come loose some how..
 
Seems to be a good diagnosis. When I read this I remembered getting a small bump on the bottom of the car while traveling along a dirt track. Had a look under the car and theres two umbilicles (presumably o2 sensors) and one has a nice big slice into it. Could be the source perhaps. Oddly enough, yesterday the car was virtually un-drivable, almost no power low down in first and massive shaking sensation through the whole car. Today its almost perfect apart from the emissions light is still on. Can it self adjust to compensate for a damaged o2 sensor?
 
Well, I made a very large error today.. I trusted a BMW dealer. Put the car in to the experts and picked it up after work. Got a bill for £350 just for the investigation. It will be a further £280 tomorrow to get the Lambda sensor replaced. :thumbsdown: :thumbsdown: :thumbsdown: :thumbsdown: :thumbsdown: :thumbsdown: :thumbsdown: :thumbsdown: :thumbsdown: :thumbsdown: :thumbsdown:
 
You're joking? I wouldn't accept that. It should be a two second thing to diagnose (read the fault code off the ECU) and shouldn't cost more than £350 all-in. Shocking :thumbsdown:
 
So..... BMW refunded £100 of the original bill for the investigation as a goodwill gesture. They had put in significant labour time and they showed me the reason... a fault report list longer than donkeys.... face. Two cylinders misfiring. Lambda sensor replaced (£300) picked the car up and the emissions light came on almost immediately. The service chap did say that the report showed two failures but they hoped to replace just one sensor to cure it. However, it seems two sensors are bust so it goes back in tomorrow for round two (and another £300)
 
Does sound a bit off to me, without even seeing the car it was fairly obvious what it was going to be, playalistic is right about time taken to diagnose.

£530 plus another £280 tomorrow :thumbsdown:
 
Two cylinders misfiring? Due to the lambda sensors being faulty? :? Never heard that before.
 
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