Nissan Repair: Timing chain noise, nissan maxima, oil gallery

Question
1995 Nissan Maxima 3.0 engine. At about 110,000 miles noise was checked by dealer and said to be caused by timing chain tensioner.A new tensioner and guides were installed .This was a upgraded part that was slightly different from the original.This seamed to take care of the problem but when car was driven at highway speeds the noise returned.If the engine is shut down and restarted 2-3 times the noise stops untill engine is run at 2000 rpm or more then noise returns.No one at shop seems to know what to do.If you have eny ideas that i can pass on it would be very helpfull.Thanks R.E.H.

Answer
The tensioner applies tension with oil pressure and my bet is the pressure regulator for the oil pump is allowing pressure to drop off too much and that is what is causing the problem.  Have them replace the regulator and pump.  Now, be sure that the engine is clean inside as I have seen a chunk of crud plug an oil gallery on and off like you describe.  So, when they drop the pan take a look for crud.  If the oil is clean you should be fine with the pump and regulator replacement.