Land Rover Repair: 1990 Range Rover classic, gasoline, range rover classic, rangie

Question
Rover misfires (miss?) under load 2500 rpm and up, warmed up.  We have had the timing adjusted/changed, all new plugs as well as wires, new guts in distributor. Running premium gas,

Answer
Hi Keaton,

nice Rangie; don't see many of them where I live.

Misfire is often associated with either not enough spark, too much air not enough fuel (rich) or not enough air too much fuel.  Since you've adjusted the timing, new plugs and wires installed, almost new dist. (did you check the coil?) - I'd start to look at the fuel feed (pump, filter). How is the fuel pressure?  
I would then take a look at the cooling system - just to make sure there is no problem within the block or headgasket problems.  Sometimes a blown headgasket can give you some misfires.  There are sensors that can detect if you have coolant mixed within your exhaust.  

Hope that helps,
JohnMc

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