I have a 1992 flareside, 5.0, standard. Every time I am running it harder than normal, say towing somthing up a hill where the rpms are higher than normal, or i am going down hill and the rpm is climbing and the engine is holding the truck back, and then push the clutch in from running it higher, it likes to go into a surging idle around 500 rpm and then it stalls after two or so surges. this is especaly annoying when im in the middle of a turn and the thing ****s the bed when i have a load on it. some ideas i have are the IAC valve or possibly the EGR valve. thanks for the help.

 

Welcome to the site. I had to edit your title as we try to run a little cleaner site here, and as a result have been recognized by Ford Motor Co. Please watch the language. IHope you get your problems solved and enjoy being here. Thanks.

 

sounds like a vacuum leak or the truck needs some TLC