Thread: 2007 Grand Prix GXP Steering stiffen warm help needed

​07 GP GXP losing power steering once warm at stand still/idle parking speed. Pump, rack, or ABS module?


6K miles prior to current issue I replaced/serviced:
Abs module was rebuilt due to internal malfunction. Fixed dash lights.


Replaced OEM 250K rack and low/high lines due to leaks and rack wander. Low pressure line did not include a finned cooler. Leaks eliminated and steering restored with no dash lights. Resolved steering angle sensor code too.


6 months after I replaced the rack, the operating temp stiff steering issue happened. Removed reservoir and cleaned out screen with brake cleaner. Also replaced hose reservoir to pump- Same issue


Replaced OEM 255k power steering pump with reman- Same issue


Replaced rack again due to rack whine and clunk- Same issue

Fluid was flushed from return line and bled with tires in the air engine off and engine on everytime.


Could the lack of a cooler on low pressure line cause the issue?
Could a defective rebuilt ABS module cause the issue and not throw codes?

The ABS shouldn't cause you to loose power assist. When you replaced everything did you bleed the air out of the system? This sounds like a bad pump to me.

If you 2-foot it (brake and gas pedals) and raise the RPM's a bit when parking does the assist come back?