IAAF acknowledges the findings of the Carly mystery shop investigation and the genuine public concern around repair pricing transparency. However, the investigation raises a number of questions that deserve careful examination before the independent aftermarket is characterised as an industry that routinely overcharges its customers.

On pricing variation

Price variation across ten workshops is not the same as overcharging. Labour rates legitimately differ by region, garage overhead, technician skill level, parts quality, and warranty terms. The cost base of the garage, the specification of the parts chosen by the client, and the backup and warranty offered can all vary significantly. A quote of £110 and a quote of £328 are not necessarily the same job. Carly’s benchmark figure of £110 is not a credible universal standard against which all other quotes should be judged.

On the diagnostic point

P0031 requires a minimum of five discrete test steps before a replacement decision is valid, beginning with a manufacturer-specified drive cycle to confirm the fault is current rather than historic or intermittent. A wiring fault or a blown heater fuse produces exactly the same DTC as a failed sensor, at a fraction of the repair cost. Any technician who read the code and quoted for a replacement sensor without completing that process has not diagnosed the vehicle. They have guessed.

It is also worth noting that the tool Carly used to conduct this investigation is, in diagnostic terms, functionally identical to a basics DIY plug-in code reader, costing under £20. In the professional setting a diagnostic trouble code is simply the beginning of the diagnostic process, not the conclusion, as it is in the DIYer world.

On professionalism and what the garages were actually asked

Carly has not disclosed what instruction the mystery shopper gave each garage. This matters. A technician who performs a vehicle health check and identifies worn brake pads, ageing spark plugs, or an air conditioning system due for attention while the vehicle is on the ramp, and reports those findings to the customer, is not upselling. They are executing their duty of care to the client. The driver retains the right to leave such items un-resolved.

Conflating professional thoroughness with sharp practice, on the basis of an undisclosed customer brief and a ten-garage sample, does a disservice to thousands of skilled, honest technicians across the UK independent aftermarket.

The question Carly has not answered is a simple one: what exactly did the mystery shopper ask for?

The IAAF position

IAAF does not accept that a vehicle driven to ten garages in an unknown state of readiness, warmth, and fault history, assessed using a consumer-grade code reader, and without disclosure of the customer brief given to each garage, constitutes a controlled scientific sample, nor a fair or representative picture of the UK independent aftermarket.