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The engine malfunction warning usually means the ecu has picked up on a fault/problem with the engine and or emissions system - in all such cases with faults like this - the car most definably needs to be hooked to a proper and capable diagnostic machine or via the Main ford dealer if preferred who will be able look into the fault more deeper/quicker to help actually find out exactly where the fault is and what the ecu has stored in regards to fault codes - this will then give a much better idea as to where to investigate further..So if this hasn't been as of yet then this would be the next step to take and take it from there based on the result of that..If its just a glitch so to speak then they can clear the memory - drive the car a few miles and then see if the warning comes back - if it is as mentioned above a glitch then the light won't come back on - if it does then they need to re-scan and see if its the same code - if it is then they need to trace the sensor/wiring/component that causing the problem...
are you just saying take it back to the dealer?
Was the light on before you had taken it in?
And did they carry out any tests on it ie:- plugging it into there diagnostic machine?
What was the results of the test if they did carry out the above?
the light was on before the service but the car was running perfectly with no loss of power or anything unusual happening.
no diagnostics on a halfords intermediate service.
the mechanic noted the warning light and recommended take it back to dealer, but found nothing at fault as far as he could see.
maybe this is a common fault as i have seen that others have the same problem whilst i have been online?
It can be a common fault "but" not necessarily all the same type fault as you may of seen online - the EML can cover a huge area of possible faults with hundreds of possible fault code definitions - If its definitely displaying engine malfunction - then as above I feel that there is an engine management fault rather than it needing a service so to speak - if that was the case then it would come up with the service indicator which as you'll know to reset is done usually by pressing the brake and throttle together and keep pressed, turn your ignition on and wait approximately 15 seconds roughly until the dash displays that the service reset is complete. Turn the ignition off ..If the Halfords mechanic has definitely checked / and inspected carefully around the engine bay as such and as much as he could "visually" just in case something has become loose or leaking ie: injectors etc..then the only way forward is to have the car diagnosed/scanned next - Taking it to a Ford dealer is one possible option and is usually the prefer method seeing as their scan tool will be that more up to date and be able to get into the fault a lot deeper than a lot of other after market tools - But it might be worth anyway trying any local reputable garages with the right equipment or even a good mobile diagnostic technician and see if they can actually retrieve/scan the system for faults further instead - least then you'll have a better idea or understanding what is actually causing the warning to flag up and what if anything needs investigated further or replaced - they will need to use the same tool to turn the light out or clear the fault memory...