Having problems with my XR2, just wondered if someone could point me in the right direction on whats actually causing the problems,

was driving down the mway at about 90-100 when all of a sudden car started to lose power, got to work and its running very rough, check oil which is low, now topped up, all plugs and leads checked and no1 plug was a little oily so cleaned and eventually replaces with a good spare i had. replaced and all sparks ok (though no1 seems a little stronger than the others) now restart and still running as if on 3 cylnders? and when i remove no1 lead it makes no difference to the idle, but all others drops alot. Drove car home and drives ok but rough and missing, still pulls strongly and got me the 50 miles home, though when i got back there was alot of run over, though thats probably cause i had a play with the timimg incase it improved it

Any help will be great ppl as im stumped till i can get a compression test done at the weekend

Engines strong service history 95000miles and only thing remotley wrong before was the valve slem seals had started to go (just) could it be a bent valve or somethin??!