Here in GA we have an emission test that requires the vehicle to be run on a roller at about 15 miles per hour, holding steady for a few minutes. On the last test, my Pathfinder almost wouldn't do this. Holding it at 15 miles per hour, after a few moments the exceleration falls off. The tester barely could hold it steady enough for the computer test to complete. Any idea what is causing this? The tester thiks it has something to do with the idler/choking device between the air filter and the intake! Is that right? Fixable or needs replaced? We don't really notice anything while actually driving except that it might be a little sluggish in excelaration - but it is old you know!
unsteady low speed idle, almost failed emmission test on 1995 Nissan Pathfinder
The item you mention sounds like the air flow meter. It measures how much air is going into the engine. It is located between the black plastic air filter housing and the rubber air intake boot to the intake manifold. Nissan do have problems with the air flow meters but the problem needs to be investigated without just replacing parts. Airflow meters set a lean code when they are failing, you get poor gas mileage and may notice sluggish off the line acceleration.