The official notice
Defect
The engine wire harness may contact a heat shield in the engine compartment. Over time, this could cause wear and result in damage to electrical wires. If this happens, it could cause problems with engine performance, including: entering idle limp mode, causing torque limitation, engine misfire, engine stall and/or a build-up of unburnt fuel in the catalyst.
Safety Risk
A sudden loss of engine power could increase the risk of a crash. A build-up of unburnt fuel in the catalyst could cause it to overheat, increasing the risk of fire.
Remedy
McLaren will notify dealers and advise them to contact each vehicle owner by telephone to advise them of this problem. The dealer will arrange for a service appointment so that the engine wire harness can be inspected and repaired as required.