Misfire and mystery warning light

[Disco Stuey]

Hi all - hopefully somebody can help me with a problem with my 1995 Disco V8i. It started misfiring slightly a few days ago - mainly under load, but it's noticable at tickover too. Today though, a warning light came on and I can't find what it means in the Rave manual (my car is a Japanese spec). The light is two horizontal lines which widen in the middle and above them are three vertical wavy lines (which look like they depict heat)?? Apologies for my crappy descriptive powers btw! The car also vibrates during acceleration, but I put that down to the misfiring. The only other symptom I've noticed is what sounds like the exhaust manifold gaskets leaking on the drivers side under acceleration.

Can anyone help me ??

[XDERIC]

new to Land Rovers, but sounds like it's in the ignition, first thing I'd due is make sure wires cap and rotor are up to snuff, and check the timing, sounds like it may be off a tad