This months (March 2026) MCR CooperWorld magazine has an interesting in-depth article on the Rover Mini SPi & MPi relating to MOT and emissions. It is Chapter 3 in a series of Technical Topics about the SPi & MPi fuel injection, electronic management systems and emissions.
Well worth getting a copy if you have a later Mini that has any problems now or in the future.
In brief summary to prepare for an MOT, ensure your SPi or MPi is serviced regularly, ideally with the aid of a diagnostic system and use high octane E5 fuel to minimise contaminants and deposits. On the MOT test day, take your Mini for a good run to burn off any contaminants on the lambda sensor and get the sensor and the catalytic converter up to temperature. Then don't let the engine get cold before the MOT fast idle tests. Also ensure the tester has correct vehicle make, model, model code, engine code, engine size and VIN so that the correct SPi or MPi test with minimum & maximum values on the database is undertaken. The full article has lots more useful information, details and background, especially when read in conjunction with the two earlier Chapters 1 & 2.
CooperWorld - March 2026.
"The last chapter of Richard Pengelly’s and Ian Beaton’s three part in depth look at the fuel injection systems of SPi and MPi Rover Minis. In their concluding chapter they deal with the vagaries of getting SPi and MPi cars through the MOT test which includes testing for emissions."
https://minicooper.o...world-magazine/
