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.

 

When I get that code, it's because the underside of the pass side intercooler coupler is pinched and letting in ambient air.

When I had the unexplained pinging 2 years ago I went through the same diagnosis process you just did........reading your post was like deja vu !

But for the pinging, in my case, replacing the DME was the solution.

 

Wow fellas, Deja Vu x 3!...I've just recently installed my 15% pulley with the correct belt, tensioner, and colder range NGk plugs...The car pulls like a mother through all gears and is consistent. However, when cruising at a good rate (50mph+) in 5th or 6th gear, it begins pinging or tick tick ticking at 4000+ rpms...when I floor it in low gears I cannot hear the ping. I also have pondered tuning, more fuel, etc but as you said, I know people have done this simple mod without any problems. Any ideas or solutions that you guys came to?

 

It only begins pinging at 50mph+ when I floor it...not while just cruising casually.

 

In your case, if not in lower gears and all the time then it's not the vac line to the fuel pressure regulator so can rule that out, and not DME.

Make sure all the plugs are tight....

If they are ok, could be a corroded contact for the #3 cylinder on the coil pack....mine would only do it in top gear on highway when accelerating....NGK coil pack and wires cured it, or you will have to keep it clean with the green scrounge side of a sponge ( nothing too abrasive )

 

I'm having the same exact issue as the OP. Did you ever figure out the cause?

Also replacing the DME (this is the ECU correct?) seems a bit excessive. What was issue in the DME that made it faulty and cause pinging?

Any other ideas as to what could cause pinging at 3/4 TO WOT in the lower rpm range? All I have is a 15% pulley, 2% crank pulley, JCW plugs and new wires. This pinging is out of control. Help!! LOL