hi,ive got a x,reg k series with 140,000 on the clock.my car has developed a strange poblem for me so im hoping someone might be able to help.the first ting i notice is the temp gauge drops off and then i can feel a bad vibrating coming from the engine.the fans are working fine and water and oil is ok.this stops when the engine is swithed off and when left for a short while it starts ok and is fine again.any ideas!