Car Forum World

Have a 2000 Durango with a 4.7 motor. Does anybody w/4.7, have a problem with the engine rpm's surging.?
the engine rpm's go up and down at idle or while driving, but looks to be more at idle. this doesn't happen all the time although. it only goes up abut three 400 rpm's at a time.

if its just doing that much its not that bad of a problem now,but you may want to check the idle air control valve on it,this will because it to do that, and also a bad zero two sensor or a throttle position sensor will do the same thing,if it has given a check engine light you may be able to have it scanned to get the trouble code from it,and this will most likely tell you what is wrong with it,auto zone will scan it free of charge,also,and there good at telling what code is what on those,good luck hope this helps.

been a certified mechanic for 36 yrs.

sounds like your redneck mall cruiser is on its last legs. next time do not purchase junk.

Could be plugged up fuel lines or filter. Have the lines cleaned, then replace the filters. Maybe the throttle body may need some cleaning.

clean up the throat of the throttle body,where the flap meets, so that it'll close completely..you may have to take the rubber hose coming from the air filter to the throttle body assy off or move it out of the way..
use some carb cleaner and move the throttle up and down to work the gum and varnish away from the area around the flap so it'll close .that should fix it what is wrong is tar and varnish and gum have got the flap to where it wont close all the way.and this makes the car idle all screwy. attempt it and see.