Ignition Amplifier Failure
code42
Fuel Fail 47 Idle speed contol valve - coil 2: Open or short circuit.
Fuel Fail 37 is either a fault with the EGR Valve or its Solenoid
In 1990-1994 XJ6 the VCM Code 44 is the code for the O2 sensor, either rich or lean exhaust has been detected and is causing the code to trigger. It could indicate a bad O2 sensor.
Fuel fail 39. EGR circuit. Faulty system operation. Is on my 90 xj6 as well- going to take EGR valve off and clean it- see what happens.
Code fuel 1 would indicate Oxygen sensor. A good information source is the Haynes Manual Jaguar XJ6 1988-94. Good luck.
I own a 91' XJ6 also and i believe when that code comes up it is as simple as your gas cap not being on all the way
Evaporative canister purge control valve circuit fault
fuel 44 is heated oxygen sencer bank A other term lambda senser the jag has two.
coolant temp sensor fault
This means Idle speed control motor (ISC) or valve