Supercharger problem

[Scottie]

I've got a friend :eek:

he is having problems with the supercharger on his S , getting bit of lagging from a standing position. he has had his cooper s for 3 years warranty runs out in two weeks the dealer has had the car for the past couple of weeks and although they acknowledge the lag the computer is not coming up with any faults anyone with any ideas to the cause.

[MartinSullivan]

If you mean for example sometimes he is at a roundabout and puts his foot down and it seems to stumble before picking up then it is a well recognised problem - that bmw have had little joy with fixing. They have tried various software fixes with no long term fix.

Many users have had success by :-

1) Resetting the ecu, and driving the car hard for 500 miles or so

2) Checking the bypass valve, several have found that there is a leak around the butterfly, which when seated properly has closed up and all but removed the stumble.

3) Installing a vacuum mod to the bypasss valve or stronger springs to the valve

4) Installing aftermarket tuning software - again this has been found to reduce the problem.

[MartinSullivan]

If the fault is as I describe do a search on Mini2 for stumble and "yo yo" to read up on fixes

[Scottie]

Thanks Martin I will pass it on to Ross ta.

[MartinSullivan]

No probs Fiona, let me know how he gets on

[Gismo]

Another small mod that can help is to fit an aftermarket throttle body, widely available, add to that a remap and your friend should be sorted :cool: