EAC Fail

[rparmenter]

Acquired a ford fiesta/ fusion 2002 back in February. Had a few prob;ems with the vehicle which come and go, however, a constant error I receive on the dashboard is EAC FAIL. Initially, when this was happening the car was starting and then would not accelerate above 15 MPH. When it occurs now the car will accelerate above this speed but will take a long time to reach 30 MPH. I had a diagnostics performed a few months ago on the vehicle and it was 'throwing out' random codes - said by the mechanic.

I eventually found a solution to this which is to open the petrol tank cap. Lots of excess air releases and the vehicle is fine after that. I have just noticed that one of the codes on the diagnostic form is the P0460 Fuel Amount Sensor and so I assume the issue is due to air getting into the system? (Please say if you disagree). Any idea how this can occur? Any changes I can do? Any fuel additives available which can block any holes within the system?

Many thanks in advance. 

[isetta]

I had a Ford Escort that kept letting me down due to fuel starvation. I removed fuel tank to check inside, cleaned out pipes, took carb to bits, checked pump etc , it went on for a couple of months intermittently.  Then I found it was fuel tank vent problem. Rather than spend more time trying to fix that properly I took the simple approach and drilled the smallest hole possible in the fuel cap. That cured it. Now I know people would say that means fuel would dribble out if the car overturned and fumes would come out of the tank, But that is exactly how old cars were up until maybe mid 1970s, they had a pin hole in the fuel cap to let the air in as the fuel was pumped out. Now and then people would fit the wrong replacement fuel cap - one without a pin hole and they would sometimes end up with a deformed fuel tank as the fuel pump would cause such a vacuum that the sides of the metal fuel tank got sucked inwards. I knew someone with a Morris Marina and someone with a Renault 5 that did that.

[Westville]

@isetta reminded me of a mini that had that problem - had to drill a vent hole in the filler cap to stop the electric fuel pump sucking the tank inside out 

[rparmenter]

@isetta Thanks for your reply. Sound's like a really good idea, I'm just thinking, my MOT is in a months time so it would be better to do it after that so it doesn't fail? Or I could get a vented fuel cap?

[EdGasket]

just drill the hole very small and somewhere where the MoT man won't notice. I've had to do this in the past on a Rover.

[isetta]

I doubt you could buy a vented cap that would fit as it’s been decades since cars had vented caps as standard. Make sure hole I small eg. 1mm max