Hello NAM folks:

The half-dozen times that I've said "As soon as this thing is running correctly, I'm selling it" has always found me so damn happy that it's running correctly that I just can't take that step of trading it in. But...I'm getting closer.

Some background:

2007 MCS
at 75k miles, many terrible things went wrong, resulting in MINI USA paying for a reman engine.
Only minor problems until 118k miles (2 months ago), and while on a trip i found myself "chugging" down the highway in Providence, RI. $900 later, a new injector, and I was heading down the road.
150 miles later, i found myself "chugging" down the road in Bedford, MA...and luckily there was a Mini dealer in Bedford. $900 later, another injector and a high pressure fuel hose.

Now we are at 120k miles (current day).

For the last few weeks I've been getting P2177 (System too lean at idle on bank 1). When it throws that code, I'm getting much less boost. At times when the car is running well, the boost is around the 12-14 range. When it is acting up, right after I push hard on the accelerator the boost runs up to about 8 and then decreases rapidly to 2-4. Also, when accelerating hard (foot to the floor) from a moving 20-30 MPH I'm getting nothing for the last 50% of the travel of the gas pedal. It's like the engine has said "nope, not gonna go there because something isn't quite right".

The last time it was in the shop (Bedford), after they replaced the injector they found that the MAF plug needed to be re-pinned because of a damaged pin. I've looked at that, put the stock air cleaner back on (took off the K/N filter and intake that I've had on for the last couple of years), and put dielectric grease on all the plugs that I could find.

Could this be MAF? MAP? Boost Sensor? what?

I've put way too much regular maintenance money into this thing and hate the thought of doing parts roulette in the dealer service bay. Any ideas what I should check from simplest to hardest?

Thanks.

 

Hmm 8 year-old car has problem at 75k dealer fixes on their dime and was ok outside some minor problems until 118k. My suggestion, sell it and buy a Corolla, Civic, Camry or Accord.

The logic of the MINI community is just baffling.

 

Probably the wiser move, but I was hoping for some helpful hints on steps I can take myself to resolve it.

 

I don't know much about the second gen cars, but I had a similar code on my 1rst gen car and it was the oxygen sensor, might be worth pulling it and cleaning it to see if that fixes your problem.

 

Not sure about 1st Gen, but this has a pre-cat and post-cat O2 sensor. I replaced the pre-cat about 20k miles back. Which one are you referring to (pre or post)?

 

I was thinking the pre-cat O2 sensor, but it shouldn't have gone bad in 20k miles.

 

my pre-cat just failed at 70,000 miles...$150 bucks later...crossing my fingers...
PITA!...changed mass air-flow now this...