Newly-purchased 2010 Focus Zetec 100 1.6 Petrol: Occasionally, the engine malfunction warning comes up with accompanying audible alarm. It seems to happen at random, although usually early in a journet. Turning off the ignition and turning it back on again resets it, but there is obviously a fault somewhere. Thanks in advance for any suggestions as to what ther issue might be, and all the best for 2020.

you need to put a fault code reader on it. having your own fault code reader is money well spent as it costs less than paying a garage to read the codes.

Goods ones from Tunnel rat electronics. less than £20 incl P&P.  Work on other makes of car also, the extra switch allows access to extra stuff on Fords.

Software to use for fords is Forscan. free for Windows.  about 6 quid for the app for android/apple

Thanks isetta, I'll get one.

5 hours ago, BathBun said:

Thanks isetta, I'll get one.

Definitely worth their money all day long..

 

However, as to random, can you shed more light?

Whilst moving/stationary, on a bend or when cold etc.?

On 1/1/2020 at 10:39 PM, WireyWhenWet said:

Definitely worth their money all day long..

 

However, as to random, can you shed more light?

Whilst moving/stationary, on a bend or when cold etc.?

When moving. Once it happened when I went over a bump, but otherwise completely random. Occasionally, the alarm will go off at random when parked, so I'm hoping locking with the key rather than the remote will stop that happening. I'm taking it to my local garage on Monday, hopefully they can spot something. I've just driven from Bath to Canterbury and back via London and it happened at least once on each leg of the journey and now the engine check light is on.

Nice you have Forscan, you will need to read the codes while you have the fault light on otherwise it will not be in the memory do not turn the ignition off as as you have found it cleats the fault.

Interesting. Does it run fine or skip a beat when it does that?

Alarm at random could be the battery being low or having a partially shut down cell in it, or potentially the instrument cluster needing a reflow to name the more common items.

As for the EML, if it skips a little almost like a misfire (or throws up misfire codes, more specifically the one for 'Random multiple cylinder misfire') then have a look at the Cramkshaft Position Sensor. Cheap enough to replace and easy enough to do yourself for a quick and easy one to rule out, but it should be solid in its mounting point and definitely NOT loose.

Hope that helps!