I have a Ford Fiesta zetec s 2005, ive been having problems with the idleing when i pull up to a junction the idleing bounces up and down and the car feels like it's going to stall! Now when I was driving to work the car lost all power and idleing was all over the place! And it came up saying EAC FAIL. I turned the car of and started it again and it ran ok the rest of the way! The idleing problem seems to be worse when the car is warm! I've had new spark plugs, new coil pack! Changed the air filter! Can anybody help? Before I take it to a garage. 

 

Thanks 

have you had the codes read as this may heip you

On 30/12/2016 at 9:14 PM, Wayne011 said:

I have a Ford Fiesta zetec s 2005, ive been having problems with the idleing when i pull up to a junction the idleing bounces up and down and the car feels like it's going to stall! Now when I was driving to work the car lost all power and idleing was all over the place! And it came up saying EAC FAIL. I turned the car of and started it again and it ran ok the rest of the way! The idleing problem seems to be worse when the car is warm! I've had new spark plugs, new coil pack! Changed the air filter! Can anybody help? Before I take it to a garage. 

 

Thanks 

Try removing the pipe and cleaning the throttle body carefully with carb cleaner. Use a soft toothbrush to do it and after cleaning the butterfly valve and Venturi lightly lubricate the sides of the butterfly valve spindle where it enters the body on either side.

(google how to clean a fiesta mk6 throttle body if your unsure)

Edited January 1, 20179 yr by Russ
Added link

Behind your throttlebody is a rubber hose, they have a common problem where they split because of the heat from the engine. Does it sound like there is an air leak? 

Mine was doing the exact same thing until I found out it was the Pcv hose.

if it's not that it could be MAF sensor or idle control valve.