Please help !

I’ve recently took ownership of my first Jag . The car has been stood for 10 years plus . I’ve managed to get it running but I’ve got a misfire at about 2500 rpm once warm ( cold it revs fine ) . I have changed the up stream O2 sensor on the LHS side ( looking from the front ) . This made no difference, so I’ve changed the plugs and still no difference. Any help would be appreciated. Thanks 😊

 

If the engine is being revved without load, the PCM does not allow the engine to go beyond ~3000 rpm to reduce the possibility of damage to the connecting rods.

Use a smart phone with the Torque app to connect to the PCM via the OBD port using a Bluetooth interface to read the fuel pressure. The fuel pressure at idle should be between 300 to 330 kPa.

 

We have to assume the Check Engine Light is on, so get an OBD2 scanner or take it to local car parts store to read the error codes if it is licensed to drive. Report back with codes.

Make sure battery is fully charged or stick a charger on it for max voltage at startup.

 

It would help to know where in the world you are located.