Mar 27th, 2012, 10:47 PM
Okay guys I really need some help...I purchased an 05 Mini Cooper S R52 a couple weeks ago. On my long drive home I noticed it pinging on acceleration from 2500 to around 5000 RPM when 3/4 to WOT and under a load. I stopped and check the spark plug wires and found severe corrosion on the coil pack number 3 cylinder. I got some sandpaper and cleaned it off and the pinging stopped about 95%. I figured I would replace the coil pack, wires, and plugs when I got home. I replaced the coil pack,wires, and installed new JCW plugs(One step colder) for my upcoming pulley, exhaust, and CAI mods. After replacing those ignition items I had no more ping. Later that week I had a 15% Alta pulley installed and a new JCW exhaust system. On the drive home I noticed the ping was back and slightly worse than before. When I got home I installed the JCW CAI with the flapper mod. No change still pings. So now I'm thinking I have a fuel issue since I just added a bit more boost and the fuel system cant keep up with the new pulley, exhaust, and CAI. So I get a fuel pressure gauge and check my pressures while driving during the point pinging occurs. My fuel pressure is 51 psi with ignition on and not running. Starting the car and letting it idle it drops to 43.5 due to the vacuum on the regulator. When I drive, it is at 51 psi and when I go into the pinging range(3/4 to WOT) it follows the boost of the supercharger and goes up to 62 psi. So i feel like my pressure is okay but decide to install new JCW injectors for upcoming ECU tune and I add a new fuel pressure regulator anyways. I also installed a new fuel filter. Get it all back together and same pinging. When I had the injectors out I saw very little carbon build up cyl 1 and 4 being the worse but not bad at all. I decided to do a couple seafoam treatments and it still pings. I've been running chevron 91 and even added a octane boost and still pings. I tried swapping MAP sensors, coil pack, wires, and spark plugs form my other MCS JCW and still have the pinging. The only time it won't ping is when the engine is cold but as it warms up it pings. The only thing I can think of now is an ECU tune to bring the timing back and adjust the AFRs if needed. I know so many people do all the mods i've done without a tune and have no ping problems, so I feel like there is something else wrong. I've gone through the ignition and fuel system and have no idea what else to check. I get no service engine soon lights. One tidbit, when I was driving it back from Houston to Boise I got a P0171 code(engine running lean) but have not had that reappear and plugs look good and exhaust is showing slightly rich maybe due to JCW(380cc) injectors. I'm up for any help or ideas anyone could offer. Thanks in advance...Sorry for the long post.