Why does it say engine system fault acceleration reduced

Is the MIL on if so what code are you getting . What is happening is the car has detected a problem and to keep it from doing damage to itself it has gone into limp mode. Limp mode disables alternating cylinders to cool them with just fuel no spark. If the temp gets to hot , the engine will shut down. You may want to check your coolant level .what temp is your engine running at .Ford has had a problem with the instrumentation cluster as well so you may want to check that out

What should I do ? I need the car to carry my disable husband around ,just bought it 3 years ago to invicta ford in Canterbury .

i know this is a old post, but the problem is common, it is the instrument cluster. the solder joints on the back of the 32 pin connector fail, the fix is not hard for someone who knows how to use a soldering iron, just need to carefully remove clocks and take apart the cluster, then re flow the 32 pins with fresh solder, then a spray over the whole board with electrical contact cleaner using a brush to lightly clean every component. once this is done, reassemble the cluster. problem solved. if you do not want to do this, send it away there are people on eBay doing this for around £50. Just type in focus cluster repair.

"Might want to check the Ignition Coils too, I can see this thread is old, but if anyone else has this problem it might help out :)

It's relatively inexpensive (apart from the Engine Coil unit which is usually around 41.99euro + Labour charge approx 1 hour) to purchase or replace this unit.

It's possible that the coils or battery arent giving enough power to the Spark Plugs to ignite. You may have recently noticed higher fuel consumption and/or less acceleration than usual. One way to test if it is a coil is to ask your mechanic to look over or remove your spark plugs (replacing if necessary) as there may be a burnt residue on them due to the coil damage. Also, when a coil is gone, you may notice a higher concentrated odour of petrol from your exhaust. This is due to wastage of fuel which the car is trying to use to ignite the sparks.

Hope this helps anyway :)"

What does mean alcceleration reduced???

I have same issue after replacing battery..my instrument cluster lights up like a Xmas tree. Lol.. then it spazzes. Wich lead me to think a fuse or cluster…comming here makes me thnk it's cluster.i will check neg terminal anyway..but it's got to be cluster…it's bump dependant..if I slap dash, something different happens…I'm no electrician, so no soldering for me…. Weather the car starts or not is dependant on slaps..or resting time