Questionin the last 2 months the "Reduced Engine Performance" message has been popping up on the message display. It seems to occur when we are driving in town, and was particularly bad one day when we were driving from store to store over short distances.
The ODB reader fingered the Mass Air Flow Sensor so that was replaced and more recently the catalytic convertor and O2 sensors were replaced, but last night the message came up again twice in short succession and then later on, which prompted the check engine light to come on.
Clearly the Land Rover technicians and Testbook4 have failed to find the root cause.
I hope you can help.
I live in Canada.
AnswerThere are many possible causes for the reduced performance message. Unfortunately the only way to sort it out is via that Land Rover test system. When the problem is not fixed it is not the T4 that will be at fault . . . it will be the technician who lacks the time or the knowledge. I don't know how to suggest you tackle this but someone if going to have to put the time in with the tester and figure it out.
The other consideration is your willingness to pay the diagnostic time. People often expect answer in minutes when in fact some problems take many hours to diagnose and more often that not multiple faults are recovered, making repair an iterative process. You fix one thing, that leads to another, and another, and so on.
Sorry if this sounds discouraging but these cars are complex, and I'm just trying to offer realistic perspective
