I have a Carrera Tunnel with dual ram external Imco steering. It has a steering cable from helm to the back. Occasionally while turning to the left the steering seems to hit its limit although it is just slightly left of center. If I turn the steering wheel the other way and then back it will turn normally. It always happens at the same spot, just left of center. I have disconnected the cable and it seems fine by itself. It has been lubricated. I can not see anything that would cause mechanical interference. It almost seems as if it is a hydraulic lock. Any suggestions?? Thanks.

which internal assist ram do you have? some times the centering valve wears , and you gfet toouchu spots in the steering.