2011 GMC Terrain jerking

PETSKING

MEMBER
2011 GMC TERRAIN
4 CYL
FWD
AUTOMATIC
111,000 MILES

My terrain jerks when I am at a stop light. This happens after I have driven a few miles like after it warms up. I always have to shift it into N while at a stop light so it wont jerk forward.

Thursday, December 18th, 2014 AT 1:12 PM

1 Reply

WRENCHTECH

MECHANIC
20,761 POSTS

So, what you are saying is that the idle speed is jumping around.

First eliminate all vacuum or air leaks in the system. You may have a bad IAC ( idle air control) but try cleaning the throttle body first. Remove the intake snorkel, have someone hold the throttle wide open for you and scrub the back side of the throttle plate and surrounding bore with an old tooth brush and some carb cleaner. Be sure to spray some into the small holes next to the throttle plate. That should help stabilize the idle. If it still has a problem, replace the IAC.