Why is this filter not being applied?

1990 F-150 hesitating at rpm's under 1000 when gas is applied changed fuel filter and tunned up?

• Answer:

  Hi! If your f-150 has a throttle body one thing that has helped in the past is,Get an old toothbrush and a spray can of throttle body cleaner.Some throotle bodies have a protective coating on the inside,so make sure the spray you buy is safe for your application.I think CRC or 3M makes a safe one.With the engine off remove the air breather,open the throttle and spray in side,spray your toothbrush and scrub the inside of the throttle body,top,sides and bottom on the inside and the back sideof the butterfly.You should see alot of black carbon coming out,alot of this is from the EGR valve,When this stuff starts building up in the body it will affect idle and performance.you might try doing this about every oil change,it works for me. A couple of other things you might look at too is to make sure your EGR valve is working properly,and also check for a possible vacuum leak,at least with what experience i have had with ford products,a vacuum leak was one of our problems. I hope this will help you and get you back on the road let me know what the outcome is!! Well all good advice but I have done that a few times and checked for vacumm leaks, and the problem is still there. I was thinking it may be my injectors I dont know how to tell if they need to be replaced or just professionally cleaned.