Hi Communicator.
Sorry again for the late reply I don't receive notifications.
I have the red injector light on the dash. When it is on the engine behaves normally which is strange because there isn't a reduction in performance (limp mode) When it goes out the engine behaves erratically and as mentioned before sometimes can floor the throttle with no response from the engine. The plug to the TPS isn't the best but couldn't see any of the pins touching. The two 5 volt references are next to each other at the end of the plug which I found a bit odd. I would expect them to be 5 volt,signal,ground. Ground,signal,5 volt. Instead I have 5volt,5volt,ground. Signal,ground,signal. I thought it may be the design of the TPS but not sure.
I did try a local garage to to get the codes but they couldn't get their equipment to communicate with the ECU (seems a common problem)
I could swop out the sensors CPS,MAP and TPS but don't want to throw good money after bad. I have heard the MAP sensor can suffer from overheating. The fault did occur last summer after a long hill climb which caused the radiator fans to turn on. Although it happened the next day and symptoms were mild. I'm still trying to get my head around how a diesel engine is throttled by the turbo rather than a petrol type butterfly valve.
Thanks again for the information.