Changed the spark plugs on a 2006 nissan pathfinder 4x4

Question

After changing the spark plugs, every thing was great. but as I drove down a long stretch of highway, I noticed that the engine would bog down , make a humming sort of noise ,and I also noticed that the tachometer dropped during all this , I can give it a little gas and it goes away , but returns. I did the throttle relearn procedure thinking this may help, but it did not work, I did unplug the throttle body switch while changing the spark plugs. also if I turn off overdrive It doesn't seem to occur. any suggestions....

Answer 1

Did you use factory spark plugs? if the only thing you did was change the spark plugs, then either you left somithing disconnected or the spark plugs you use are not the correct ones or are damage.

 

You couls also try disconnecting the car battery for about 30 miutes to reset all system and then perform the Idle Air Volume Learning procedure. Instructions here: http://nissanhelp.com/diy/pathfinder/projects/nissan_pathfinder_idle_air_volume_learning.php