Nissan Repair: 2000 xterra

Question
We bought a 2000 xterra and after a couple of major engine repairs we decided on the 50,000 japanese engines. Had a pro switch out engines. Since the switch it runs great except when you shift into reverse or drive. The problem happens only after it has warmed up. When you shift into gear the idle drops down then the engine starts sputtering and misfiring and sometimes dies. I took it to a shop and after their diagnostic they said it was the plugs and wires. I switched those out and it still does the same thing. The mech who switched out engines said he expects a clogged injector. With all the repairs and engine swap we have about $10,000 into a $4000 vehicle. HELP

Answer
Hi Michael -

The first thing I would check for is a vacuum leak. Check all the vacuum hoses for proper connection or breaks and cracks.

A good test is to get some injector cleaner and while the engine is idling, spray it liberally on different parts of the engine, especially along the intake manifold areas. As soon as the idle improves, note where you have just sprayed and you have found the problem area.

Hope this helps -
aloha
Calvin