Hi All,
Customer complaint is that it cuts for 1/2 second, intermittently and between speeds of 40 and 70mph, ok above and below that range.
On roadtest what I felt it was doing was hunting in that speed range rather than outright cutting.Felt rather like EGR problems but vehicle not fitted with EGR.
At the dealers it has already had a new MAF and ECU update. Their next step would be to "check the front harness".
No codes in OBD but one code if I talk to it as a Ford "P1565 speed control command switch out of range" Which was as reported by the dealer. Vehicle not fitted with cruise control so I suspect this may be a complete red herring.
I cleaned and put contact treatment on all the connectors to the MAF Throttle body etc. On roadtest it seemed much better.
On another roadtest this morning it briefly developed quite a stutter at 40 mph and when I brought it back to the workshop it had an intermittent misfire at tickover. I am now thinking it has a plug or coilpack failing. Unfortunately the three drivers side plugs are under the plenum. Any ideas how I can determine which cylinder is in trouble other than waiting for it to set a misfire code?
I nearly didn't take the job as I don't have any decent Jaguar diagnostics but it does seem to talk reasonable Mondeo with plausible live data values.
When it was exhibiting the problem it did seem as if the STFT was changing from -0.8% to +8% (or thereabouts.