Hi all
I've got a '94 XJ6 4.0.
It's developed a fault as follows:

Whilst driving along, the car cuts out for a second or so before restarting. It happens especially after tight cornering, or, accelerating up motorway sliproads (although these are generally after a roundabout etc!). However, it also occasionally happens when driving along at a steady speed.

The car runs absolutely fine apart from that, with no other known faults. When the engine cuts out, the CHECK ENGINE light comes on until the car restarts, and then it goes out again.

It's been converted to LPG but it does it when running on both petrol AND lpg.

Any suggestions as to what it could be?

Regards
Richard

 

Since it happens on both LPG and Petrol, it's unlikely a fuel delivery issue.

Typical symptom of a failing Crank position sensor is stalling after vehicle reaches operating temperature, but then the engine won't restart until it's cold again.

Typical symptom of a failing Cam position sensor is stalling after vehicle decelerates, but then the engine Will restart immediately.

My vote in the early going is a failing Cam position sensor, but wait for more capable diagnosticators? to chime in.

 

Check ECU relay, common problem. On a second read I realized your dash lights give you a light show, this is also common with bad coils. First, take of coil cover and take a look at them while the car is running, this must be at night, if you see any of the coils light up you have found your problem..

 

Old spark plugs will cause stalling. A must-do maintenance item if the plugs are old (or of unknown age). Use the standard Champion RC12YCC plugs. An inexpensive fix if you do it yourself.