yes i have a 1987 f-150 4.9 straight 6, efi. sometimes when i am driving it the throttle will just surge up real hard. and sometimes darn near die on me. and others it will just run fine. i have replaced the throttle air control valve and it still does this. i have found a valcuum line that is all dry rotted but not sure if that would be causing the problem. i have been told to replace that and or the throttle position sensor. tight on money so wondering what will be my best bet.

 

no body has any help. i have 41 views and nobody has any ideas.

 

definately start with the vacuum line. Vacuum leaks can cause the vehicle to do funny things. I'd check all the lines in the throttle body and intake area while you are at it.