hi all.i have a few problems the first is when i start the engine it blows a lot of smoke (started about a month ago).the second is when in cruise on a slight incline it drops back a couple gears and revs out to around 4 on taco then the oil light comes on.when i turn engine off for a few minutes then on again the light is off,the away i go again.it only comes on when in cruise.plenty of oil.just serviced.sorry 2007 3 ltr turbo deisel auto.also oil coming through back right hand side of intercooler.about 3 inches by 1 inch.any help would be much appreciated.