Was a little concerning and I can't head to my mechanic until next weekend so wondering if anyone has any idea. 09 Mini Cooper S Clubman. First time with any boosted car and first time manual driver. Turned out of a parking lot onto a busy road so i got on the gas to get up to pace with other vehicles (50mph). Shifted @ ~5k from first to second, reached 5-5.5k in second when i got a rattle from what felt like below the car, but more towards the engine. Nothing visibly wrong. I was ready to shift so literally the instant it happened i slammed on the clutch and threw the shifter into neutral and just coasted for a bit. Looked in the rear view and i could see a puff of darker smoke clearing out from behind the barn doors. Any ideas?

Only modification is K&N intake. 78k miles. oil change and coolant flush at about 76k.



SOLVED: Exhaust clamp lost a screw. High RPM cause enough pressure to open it up.

 

How does it run after the incident if it runs at all? Sounds really bad from your description, sounds lIke your though a rod or piston.

First thing first preform a compression test.

 

LOL... Lets not exaggerate here.

omgitstista, what you experienced is called super knock. Were your valves ever walnut blasted? Was your high-pressure fuel pump ever replaced?

 

It's been running fine. No smoke on start up or while driving. Haven't opened her up since. I haven't had either but there's no way for me to tell if the fuel pump was replaced by the previous owner without knowing what dealer they went to since I assume they would have done it under warranty. I was planning on doing the walnut blast at 100k miles even if the valves don't look bad just to keep it fresh. A friend of mine who's had a lot of forced induction vehicle experience said it could be a loose clamp somewhere early on the exhaust that opens up under the high pressure.

 

If I were you I wouldn't wait till 100k, if only you knew how bad the valves can look after just 50k. It's choking the engine and will cause all sorts of problems.

 

Please read the first reply and pull the engine.

I'm sure you can do a deal with that member to do a forged rebuild for you he has a lot of experience doing those rebuilds, actually if I remember correctly he's running a MANIC tune so can also advise of tuning options as well.