Ok I need a bit of help on this one because I have run out of ideas at the moment. I have a 2002 Mini S R53 120k miles that I have bought and been rehabbing. Most of the issue I have fixed and cleared a few codes but I have two that I can't seem to get rid of. The Code is P0507(High Idle) and it has a P1477.

Upgrades to my car- CAI, 15% alta pully, Detroit Tuned BPV, and it has a cat back magna flow exhaust, and me as an owner.

Here's what I have done so far, replaced Harmonic Balancer because that was putting it in limp mode. Issues after that caused me to decide to smoke test it and it had a huge leak from where the green gasket(supercharger to air inlet) where the air comes from the throttle body to the supercharger. So with that I decided to go ahead and take the supercharger off and service it since I had no idea if it had been done before. When I did this I replaced the Idler tensioner pulley, Leak diagnostics pump, waterpump, installed a Det tuned BPV and replaced the fuel vapor vacuum hose?(the one that goes from the fuel tank breather valve to the throttle body) and the fuel tank breather vacuum line because those had a lot of dry rot on them, and all the gaskets in between. Started it back up and still had some the pre-metioned codes and an O2 code, so I went ahead and changed both O2 sensors. That cleared the O2 sensor codes but I am still stuck with a high idle about 1000 RPM. Also the fuel pump died on me during all this and I replaced that and the fuel pump sending unit/ new filter while I was at it. Last thing I did as a longshot was change out the MAP and TMAP sensors.

I did another smoke test and I am still getting a little bit of leak around that green gasket(supercharger to air intact duct) but I have read that it leaks almost all the time anyway.

Looking for trouble shooting suggestions at this point as I am out of ideas so I hope someone can help or has maybe had this issue. Thanks.

 

Ok well I did a lot of work to this and still had the idle issues. Honestly what I think was the main issue causing the most trouble was the vacuum leak from the throttle body to supercharger inlet tube. Once I got that fixed the car idled normally. I was told by a local shop that specializes in Mini's that the fuel pressure regulator was leaking a bit and dripping into that area and adding excess fuel into the system, however personally after pulling all that apart I didn't see any indication of that.

Anyway hopes that helps anyone else in need, that vacuum leak there was clearly a bigger deal than I gave it credit for.