cable might be seizeing up might make bonnet keep opening. with bonnet up, keep trying cable see if it is working freely. squirt wd40 down cable from bonnet end. or could be bonnet catch may be sticking wd40 all this too. or bonnet catch might need adjusting. usually 2 bolts either side of catch in slam panel. slighty loosen and lift up catch slightly then tighten. check bonnet sits right when closed. or could be all 3 of these.
me, June 2009