Has anyone had any Check Engine Problems for a 2006 Mini Cooper S Automatic? After 7 months of having the check engine light appear every month and the dealership not being able to find the problem, they just replaced the thermostat and the heat sensor. The mileage on my cooper S is only 19 miles city and 22 miles highway. I believe whatever is wrong with this lemon is affecting the gas mileage. Lets Motor means trips to the Mini Dealership.
Rizoll, Looking at your mileage figures, my guess would be your oxygen sensor is bad or intermittent. This should show up on Towne's plug in analyzer, but it sounds like it might be hiding somehow. Check this out: "The oxygen sensor tests the exhaust gasses and determines how much residual oxygen is in the exhaust. By crunching some numbers, the computer then determines what the air/fuel ratio actually is based on what the oxygen sensor tells it. Pretty nifty, huh? Also called the O2 sensor, the oxygen sensor is a critical component in your fuel injection system. If your oxygen sensor isn’t operating properly, your computer doesn’t know the rate at which to inject additional gasoline. The end result is that a fouled oxygen sensor causes the engine to run rich, which can then lead to catalytic converter failure." A telltale sign of this happening for sure is a rotten egg smell which will come and go at different times. Another thing you can check yourself if you are at all mechanically inclined, is the air box (where the air cleaner is). The Mini takes in air from below, and runs it UP through the filter and on into the engine. On my Mini, I found a virtual "nest" of leaves, and other debris directly under my air cleaner. It was hard to believe it could have occurred naturally, so I suspect a mouse was at work! Hope this helps, and good luck! Bill aka "Cogman"
You are so amazing. It was a temperature sensor after all. Perhaps you should work at Towne Mini because it took them 7 months to find the problem even though I told them that the check engine light went on after I used both defrosters and the heat set on high and no matter how I drove the car, the gas mileage kept decreasing. They replaced the thermostat twice and finally replaced the temp. sensor. I now get 24 miles highway which isn't great still. I asked Mark from Towne Mini if driving with the check engine light was 4-5 days at a time until my scheduled appointments for 7 months affected the engine and he said No. I'll keep an eye on the catalytic converter failure like you mentioned because knowing my luck, it's going to happen.