Also, I forgot to respond to you regarding the fuel trim code, I have never had the code pending or come up. I think my old HPFP was actually still good, but I replaced it.

So I have a new Valve cover, HPFP, I have done a carbon blast/seafoam, and I have a new primary O2 sensor. I may need to change the secondary (downstream) O2 sensor. I have already tested the MAF and tried replacing it with a new one, which made no difference. I have checked the sensors on the manifold and charge pipe, they were clear of any gunk. 

I have done many smoke tests and leak tests with starting fluid and sensor cleaner. The only leaks were from my valve cover to my catch can hoses, which has been fixed. Part of me is wondering if the extra volume of air in the catch can is throwing the code.

Checking compression is the only thing I have yet to do, I'm terrified I might have one cylinder way out of wack, but I need to do it. I know it will mean either looking at other parts of the car, or rebuilding the motor/getting a new motor.


Has anyone ever chased this code before? I have spent thousands on new parts trying to get the car to behave normally. 

Have you replaced the high pressure fuel pump, valve cover, O2 sensors?

Have you checked compression to see if there might be carbon buildup on the pistons?

If you had a significant air leak after the airflow meter and is running lean (as it would be pulling more air in than it thinks, thus underfueling the engine) then it should also be throwing a long term fuel trim (LTFT) code as well. (P0171.) Are you getting this?

Locating a leak is tough. A smoke machine is the way shops use to find leaks, but it's not a tool most people can afford to have in their garage. There are some do-it-yourself smoke machine plans out there if you want to try it.

The way I use is with carburetor cleaner spray. Connect a monitor to check your long-term fuel trim readings from the oxygen sensor (cheaply done by using a smartphone app like Torque and a inexpensive ELM327 adapter that fits on the OBD-II port to talk to the app) and start spraying connections and pipe junctions. 

If you spray on the leak with the engine idling, the fuel trim will quickly correct itself and you may even hear the rpm change. The worst case scenario is that the leak is in the middle of a pipe or tube. Then it's a lot less likely you'll spray in the right location to find that leak, and there, a smoke machine works better.

I will say though that when I had such a problem, the factory/dealer (Jaguar not MINI) could not find the leak with a smoke machine, whereas I did find it with the carb cleaner trick.

Anyway, if there's no LTFT anomalies, I'd bet there's no leak, and the code is a side effect of another issue (like a bad sensor.) Sensors can fail for other reasons besides dirt and grime


Good luck!

2009 MCS - 86Kish - stock tune with many goodies (no aftermarket parts that would require a retune).


I've had this code recurring since I replaced my cooling system parts (water pipe, thermostat housing, water pump). 

Sometimes it is paired with misfires and P0300, other times it's by itself. I can have the car never throw the code, but have it pending and get into limp mode. I can also have a CEL come on for it without limp mode until I hit 100 miles since a code clear. 

I have replaced so many parts chasing this problem, so my car is running wonderfully, minus this code and its ties to limp mode and a CEL. 

I have no boost leaks, my sensors seem to be working properly and aren't gunked-up. I have posted about this before but only receive replies from one gentleman, so I wanted to see if anyone else can weigh in. 

Since I replaced the turbo, the car has been running too lean and my oil is smelling like gas. My guess is that the car is reading the unmetered air and adding too much fuel to compensate, but this could be paired with the problem, and not the symptoms. 

Any ideas?