Currently our 2000 Disco II is at our local Land Rover mechanic and is currently displaying these 2 codes. A little background is in order. This vehicle recently suffered from a blown head gasket and this has been repaired. But currently we have these 2 codes shown at ignition. The MAF has been replaced with the original Land Rover unit but the codes once cleared out continue to reappear. The truck seems to run fine. What are your thoughts?