Need some help here. Got 200K on my 94 4rnr and the other day it started this knocking noise. It's not comin from the block, it sounds like right under the intake manifold. It gets louder and faster when I hit the throtle. It does go away when it warms up. It hasn't lost oil pressure or over heated or lost compression. It runs fine only it has that knocking or say ticking noise. Talked to a machine shop and they said my best bet would be to rebuild the motor @ a cost of $3800. Any help would be appreciated. Stuck in the driveway!!!!