Jerking

[Stefanie1976]

I have an 2003 Expedition 4.6 and I have seen several issues on here with the same problems. It started out when you dropped the RPMs and the speed down to about 40 MPH and when slowly pushing acc. the truck will do 1 to 3 small and quick jerks. I have changed the boots and springs and nothing has changed. My SES light is not on so I cant put the comp. on to get any codes. Now that I have changed the ing. boots it is now doing it more when I was on the highway running higher and steady speeds. I have seen alot on here about changing the coils but I dont want to go spend all that money if it is not needed. Can someone give me some ideas before I go ot and spend money and fix things that arent needed.

 

[walnuts4x4]

i'm gonna say low grade miss from a COP.... either wait a while and it will trip the light or look into getting COPs from ebay.... global automotive or UNEEK on ebay sell the set of 8 shipped for around 100...

also a dealer or someone with the right tools can run a power band test and see which cylinder is having the low grade miss