How to quiet lifter tapping on 05 Nissan Quest?
My 05 Quest has a loud tapping noise from the engine compartment. The noise does not stop until the engine is off. Multiple visits to various Nissan and independent repair shops all point to faulty lifters. These mechanics concluded that maybe the oil pressure wasn’t high enough for the lifters to function properly. The van has 115K miles. I tried the following:
1) Lucas oil treatment which worked to quiet the tapping only momentarily
2) Seafoam as an oil additive to no effect.
At this point I’m skeptical about using any other additives.
So what has worked on other Nissan Quests?