g;day sam it could be the vvti pulley lexus say its not repairable and dont sell the oring seal.but it is doable you just have to remove it remove the 5 10mm bolts be sure to mark it so you can put it back the same way.once apart you will see a large oring it will be hard and brittle.remove and clean get a new oring from a seal supplier.or you can just use rtv ultra grey.put back together and roberts your rello.good luck