Low rev misfire, any ideas please?

[Fatboy chim]

My 4.0L is still spluttering at low revs (under 2500) it only seems to happen when its really hot, say , after half an hour, its only with part throttle that its a problem, if you give it the full beans it coughs then takes off as usual.
I have cleaned the stepper and throttle butterfly and neither cured it.
I have now checked plugs/leads are secure.
Could they give these symptoms if starting to fail?
I have ordered a new temperature sender
(SNB 802??? arrives Friday)is this a likely candidate?

Any help or ideas would be very welcome

[jonywishbone]

I had a similar problem to this and replaced a lot of things in your list. In the end I found the problem very easily on a dark night. The layout of my distributor means that the top of the leads where they leave the distributor actually touch the Aluminium tank on the cooling system. When the engine got hot the insulation on my Magnecor leads appeared to degrade and allowed the No 1&2 cylinders to spark through the lead onto the tank at low revs. I cured it very simply by cutting two sheets of plastic from a milk carton and put them in between the leads and the tank. This stopped the short and I had a perfect running car again. Suggest you have a good look under a hot bonnet on a nice dark night and give it a few minutes to let your eyes get adjusted.

Good Luck