Misfiring Discovery II 2000 but fine on cruise control

Hi, my Discovery II 2000 manual has developed an occasional misfire and apparently belches out cloud of black on misfire. It is fine at idle but at 1500 rpm it misfires every couple of minutes. Driving it misfires intermittently then the engine light comes on. Turn ignition on and light gone, idles fine but driving it misfires. The odd thing, if I drive on cruise control (flicking it on and off for corners etc) it's fine.turn cruise control off and drive normal it misfires! Happened few months back but was fine the next day. This time it's not gone away.
Help!!
Has anyone else experienced this weird fault?
Any suggestions welcome as I'm stumped.
Thanks

Hi, if it works normal on cruise controll and idles well my first call would be the throttle position sensor... but if the MIL light was on the best way to find something out is to plug in a tester and read the fault codes cos there must be in the ECM memory

sierrafery said:

Hi, if it works normal on cruise controll and idles well my first call would be the throttle position sensor... but if the MIL light was on the best way to find something out is to plug in a tester and read the fault codes cos there must be in the ECM memory

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Hi
can this be recalibrated with the Nanocom evo 2

cruiser524 said:

Hi
can this be recalibrated with the Nanocom evo 2

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No, it's not a recalibration matter...but it can be checked if it gives good inputs or not

sierrafery said:

No, it's not a recalibration matter...but it can be checked if it gives good inputs or not

Click to expand...

Thanks for the reply