I bought a 05 reg 1.6 tdci this week and when I was driving it home on the motorway a message appeared on the dash saying “engine system fault” and the car seemed to lose a small amount of power. I was stopped at lights so I decided to turn off the engine and turn it back on and the message disappeared. That was grand for a bit and got back on to the fast road and when I got to around 120km/h the car stopped accelerating and the message re appeared. It only seems to happen when I go on the motorway, it’s grand at slower speeds in town and on secondary roads. Any of ye experience this problem at all, and how to fix if possible?

The "Engine System Fault" message is just a generic warning message which can be caused by lots of different problems.

The only way to find out what is actually causing the problem is by reading DTC codes with a suitible Ford specific diagnostic system. Preferably when the warning message is active.  

The guy I bought the car off said it is due a service so would that resolve the issue do you think ? 

2 hours ago, coreykelly said:

The guy I bought the car off said it is due a service so would that resolve the issue do you think ? 

Make sure your fuel filter gets replaced I'd say this is most likely your culprit

I had same prob but on a 06 18tdci it could be a few things , but first I would replace fuel filter as said using only a Ford one and use some rubber grease on the houseing rubber washer . People neglect the fuel filter as they can be a nightmare on the 18 not sure about the 16 , put some fuel treatment in as well and some good fuel then run it hard for a few miles . The engine fault light can come on for a load of reasons , split  hose stuck turbo vanes dirty sensor low fuel pressue  . I know that the 18 Tdci hates having dirty fuel and air filters so start with them things first I can see the 16 being the same. 

On 26/12/2017 at 5:57 PM, Oldschool said:

I had same prob but on a 06 18tdci it could be a few things , but first I would replace fuel filter as said using only a Ford one and use some rubber grease on the houseing rubber washer . People neglect the fuel filter as they can be a nightmare on the 18 not sure about the 16 , put some fuel treatment in as well and some good fuel then run it hard for a few miles . The engine fault light can come on for a load of reasons , split  hose stuck turbo vanes dirty sensor low fuel pressue  . I know that the 18 Tdci hates having dirty fuel and air filters so start with them things first I can see the 16 being the same. 

I changed my fuel filter this morning and it was still giving the engine system fault message, so I plugged it in and it gave a code P0299 underboost/overboost. Any ideas where to check for leaks or anything? 

On 25/12/2017 at 8:03 PM, Ryan_Tango said:

Make sure your fuel filter gets replaced I'd say this is most likely your culprit

I changed the fuel filter this morning no luck, cheers anyway for trying to help.