1994 Jaguar XJ6 Cold starting

My first thought would be the coolant temp sensor telling the ECU that the engine is warmer than it is.
Therefore giving the engine too lean a fuel mixture to start. The CTS may be able to do this and still in range enough not to trip a VCM code. A quick test; find a vaccum port somewhere on the intake manifold. Where you can unplug a vaccum hose. Doing a cold start as the engine start as the motor starts to turn, spray a little shot of starting fluid or carb cleaner into this open port. I wouldn't do this ahead of the MAF meter. It might damage it. If i'm correct, the motor should pop right off. If it does, then I would look at the coolant sensor.

This is 16 things to check I would look towards #3 first

1 Inspect Fuel Filter Clogged or dirty fuel filter

2 Inspect Air Filter Restricted or clogged air filter.

3 Inspect Fuel Injector Cold Start Valve Faulty cold start valve or circuit.

4 Inspect Battery Damaged or faulty battery and/or connections.

5 Inspect Wireset Damaged, worn, or deteriorating spark plug or coil wire(s).

6 Inspect Spark Plug Fouled, damaged or broken spark plug(s).

7 Inspect Starter Damaged, worn, defective, or faulty starter or starter related circuit.

8 Inspect PCV Valve Plugged or damaged pcv valve.

9 Inspect Throttle Position Sensor Faulty throttle position sensor or throttle position sensor circuit.

10 Inspect Air Charge Sensor Damaged or faulty air charge sensor or air charge sensor circuit.

11 Inspect Air Cleaner Temperature Sensor Damaged or faulty air cleaner temperature sensor or air cleaner temperature sensor circuit.

12 Inspect Fuel Injector Pressure Regulator Faulty fuel injector pressure regulator or circuit.

13 Inspect Fuel Injector Plugged, dirty or poorly connected fuel injector.

14 Inspect MAP Sensor Improperly connected or faulty m.A.P. Sensor.

15 Inspect Mass Air Flow Sensor Improperly connected or faulty mass air flow sensor.

16 Inspect Fuel System Pressure Incorrect fuel pressure being delivered to carburetor or fuel injection system.