Today when I started my truck it idled at 1200 rpm. I left work and drove about 3 miles then it just fell to an idle. (850rpm) The engine light came on and the accelarator pedel was dead. I turned off the truck and restarted with no difference. I was idleing back to town and then the accelarator begin to work again, but it idled at 1200 rpm again . I took straight to the dealership (about 4 miles) because I didnt want a big tow bill. Any thoughts on what is happening? (2001 HO)