Case Study
Mini Cooper S in Limp Mode – Catalytic Converter Replacement
Our customer brought in their 2007 MINI Cooper S in limp mode, with the warning light showing on the dashboard. They had also noticed a general lack of power before the light came on. Our MINI specialist technicians carried out a detailed diagnostic assessment, which ultimately led to a catalytic converter replacement.
Fault Codes
2D8C – Knock sensor electric
2D50 – Super knocking
2885 – Boost pressure control deviation plausibility
Common Symptoms
- Car in limp mode with a warning light on
- General lack of power
- Low boost pressure under acceleration
- Previous MOT failure on emissions
MINI Cooper S Diagnostics
A fault code scan returned 2D8C, 2D50 and 2885. A visual inspection found the turbo intake pipe had come loose, but securing it didn't cure the fault. A road test while monitoring boost showed it was too low, reaching 1500mbar before dropping to 1022mbar. An intake smoke test found no leaks, the wastegate held pressure with the rod moving as it should, and key-on boost readings were correct. With possible causes including coked intake valves, a blocked exhaust or intake, a cylinder issue, a turbo or wastegate fault, or a wiring problem, we scoped the boost sensor, throttle pedal and wastegate control, inspected the valves with a borescope and carried out an in-cylinder pressure test. The spark plugs showed white deposits from overheating. Removing the front lambda sensor to test exhaust back pressure showed it was fine at idle but rose to 791mbar on a snap throttle, a clear sign of a blocked exhaust.
Vehicles Affected
MINI Cooper S
- MINI Cooper S 2006
- MINI Cooper S 2007
- MINI Cooper S 2008
- MINI Cooper S 2009
- MINI Cooper S 2010
- MINI Cooper S 2011
- MINI Cooper S 2012
- MINI Cooper S 2013
MINI Clubman Cooper S
- MINI Clubman Cooper S 2007
- MINI Clubman Cooper S 2008
- MINI Clubman Cooper S 2009
- MINI Clubman Cooper S 2010
- MINI Clubman Cooper S 2011
- MINI Clubman Cooper S 2012
- MINI Clubman Cooper S 2013
- MINI Clubman Cooper S 2014
Peugeot 207 GTi & 308 THP
- Peugeot 207 GTi & 308 THP 2007
- Peugeot 207 GTi & 308 THP 2008
- Peugeot 207 GTi & 308 THP 2009
- Peugeot 207 GTi & 308 THP 2010
- Peugeot 207 GTi & 308 THP 2011
- Peugeot 207 GTi & 308 THP 2012
- Peugeot 207 GTi & 308 THP 2013
Catalytic Converter Replacement
The back pressure results pointed to a blocked catalytic converter. This MINI had failed its previous MOT on emissions and only just passed the retest after a catalytic converter clean, so it's likely the catalyst was already on its way out. To restore the lost power, we stripped the necessary components from the engine and fitted a new catalytic converter and gaskets.
Resolution
With the new catalytic converter fitted, the MINI Cooper S was back to its powerful self. Our customer even told us the car felt better than it had since they bought it.
Are you experiencing a similar issue?
Book in your vehicle for diagnostics today.
Collection & Delivery
We can collect your vehicle and deliver it back to you.
Hire Cars Available
Stay on the road with our hire cars.
Smooth, Hassle-Free Service
We make the process easy from start to finish.
I would strongly recommend Cedar Garage to anyone who's car is experiencing issues. Despite being told the issue with my car was quite complex, the team at their German Car Specialist site were quick an efficient at finding the issue and fixing it. They went above and beyond to get my car back on the road quickly and safely. I was always aware of what was going on as they maintained great communication, even when the supplier sent them the wrong part which their front of house team dealt with swiftly (even though it wasn't their fault). I felt like they really cared about helping me out and I will definitely be returning.
Danielle
Customer Review