So two weeks ago I completed a major wrenching session on my 02 mini cooper S.

After a gas fill-up on my way back home one night, I noticed the car was making a turbine like sound. Instantly I said oh no, my supercharger is dying. I was ten minutes from home and it was like midnight, so I decided to just drive it home. On the way, I got a scary intermittent sound like there was a tree branch scrubbing the road below the car. When I arrived home the engine sounded like there was no oil in it. Being broke at the moment, and too scared to drive the car all the way to the shop, I started to dissassemble the front of the car in my garage. Removed the supercharger from the car and opened it up, all looked ok. I put it back together, and changed the oil in it. Found out my alternator was SHOT and was about to explode.

While I was there, I decided to replace the crankshaft sensor and water pump o-rings. I also installed a new fan relay, a 15 % pulley, and did the vacuum gain system mod. I also installed iridium colder plugs. After some waiting for all the parts to arrive, I put everything back together, two weeks ago.

When I first started the car, I got a check engine light, but everything worked fine for a week, and I must say the change in performance is surprising. I then noticed that I forgot to replug the connector that goes into the black cylindrical vacuum thingy above the accessory belt. The check engine light then went away on its own. Everything perfect for another week.

Then yesterday evening, I was at my girlfriend parents' place. When it was time to leave, my girl asked me if she could drive my car back home, and I bring back her car. I said yes, but as soon as she pulled away, I noticed the mini's exhaust sounded like SSSSHHITTT. I was thinking ''oh no, don't tell me my car sounded like that for all that time and I didn't know''. But two minutes later she pulls over at a stop sign and tell me engine is making strange noises. I told her that I didn't know what she did to my car because it worked flawlessly that day, but since we were 6 miles from home I told her just drive it home and I'll see then.

Arrived at home, she tells me that she accidentally tried to start in 3rd gear, making the engine rumble. I thought everything was normal so I didn't check. Then this morning, I started the car and idle was rough, and pressing the gas pedal seemed to choke the engine rather than raising the throttle. It was impossible to drive, until I found out it was possible to drive, if raising the throttle very progressively. And the weird thing is I was having the asc light on, and pressing the switch did not turn it off. I then rest the ECU and curiously, the ASC light is now off but I have a yellow check engine light.

Sorry for the long post. Tried to describe symptoms as best as I could. To make a long story short, it looked a hell lot like a map sensor issue I had on a different car. But can these go so bad all of a sudden ? And besides, a faulty sensor wouldn't be fixed by a mere ECU reset ? Or would it ?

Any thoughts welcome

 

Today the check engine light was gone. Still don't understand what happened.