I have multiple fault codes on my 02 XJR.
90% of the time it is running fine. Now and then an orange warning light appears with the message: engine protection mode. It seems to be driving ok.
Recently it happens that when starting the engine goes in safe mode, with some mentioning of traction etc. This happened also last year summer (Spain, 30 degrees celcius) and then disappeared.
I have to admit that I am diving ound without my themostat (no time yet to replace it).

The fault codes I now get are:
P0128 - thermostat related: makes sense
P1121 - Throttle position (sensor)
P1230 - Fuel pump relay
P1646 & P1647 - O2 sensor bank 1/2

I will start putting the thermostat, reset the codes and see what happens.
However, if I need to replace sensors and espacially fuel pump, I need to order asap. Parts are hard to get here.
Any thoughts?

 

Initially I would try to solve one issue at a time to see what clears as you proceed. #1, get a thermostat in it, it can cause irregular heat distribution and thus throw ghost codes. Clear codes and monitor.

The TPS 1121 may be either the TPS itself or the pin connectors to it, which have had issues in years past and I believe the replacements are gold. Also, meter the TPS, lots of videos on Youtube.

The 1646/1647...if they do return after thermostat install and code clear, you may need to review this... https://www.jaguarforums.com/forum/x...cement-195018/

The 1230 I would review this thread... https://www.jaguarforums.com/forum/x...roblem-197279/

 

Not a good thing, running the engine without thermostat - it will run hot all the time. In addition to controlling the engine temperature, the thermostat also closes the bypass when the engine reaches the normal operating temperature. If the thermostat is removed, the bypass will always be open so you will have only about 50% of the hot coolant that exits the engine running through the radiator to be cooled. The other 50% of hot coolant that exits the engine will go back into the engine without being cooled.