Engine Misfires

[marshpa]

Hello. Having problems with my 21 plate Puma ST. Beginning of June started misfiring - same confirmed on my FordPass app. No rhyme or reason - would simply start juddering and then EML flashing orange would come on. And it sounded rough idling. Restarting car solved it. Went into Ford garage for a week mid-June - they couldn't replicate it. Happened on 29th June and was taken into Ford garage on 30th. No codes stored, and again couldn't replicate it. Last nght driving on 30mph road, same thing happened. Pulled in and turned car off and on and back to normal and been driving fine today including the motorway. I am really stuck as to what to do. I can't afford for it to go in a week again (had to pay for a hire car for a week) and the next time the garage have said it will cost £240 + VAT for diagnostics. Its done 25,000 mile and been service as planned. Still under warranty of course. Looking at things could be a faulty ignition coil but I don't see why should I replace it myself - even if I could. Any advice? Should I contact Ford direct? Thanks.

[marshpa]

Screenshot from the FordPass app.

[robgee]

It might be worth dropping a line or contacting Ford on the number or email below. With the details and a screen shoot and ask them to assist.

Ford Customer Relationship Centre, UK
Phone: 0203 5644444
Email: ukcrc1@ford.com

My knowledge of engines is non existent so hopefully someone more knowledgeable will give some advice

[Rizmo]

Also try a tank of top quality fuel. There is info elsewhere on the forum.

[Rizmo]

Although not easy a video/audio of the symptoms presented to your dealer would help your case.

[Rays1]

Don't see how Ford direct will help you. At least and unfortunately not until you car has been diagnosed.
Definitely sounds like a spark ignition issue. If it were me I would start with the plugs. If you're able, remove and visually check and compare each for coking or increased wear which is typically seen in the form of increased spark plug gap and degradation on higher performance engines. If so then replace as a set. Iridium plugs are usually preset. As plugs go those on the ST are not cheap. Then if not the plugs then yes it could be a coil breaking down.
But hey thinking about it if you look at the service intervals at 25k (2yr) the plugs will need to be or should have already been replaced regardless. Charged an a extra I believe by Ford, (could be wrong on that?) so if you can do it yourself so much the better. Had my 2yr service at which point the plugs were replaced (my ST has only done 11k) without even asking service.
Did they replace yours at 25k or prior? Worth checking I think!
Mind you my ST is now running M260 and so will insist the plug are replaced at every yearly service interval.

[Pawprint66]

Air mass flow sensor faulty or failing?

[marshpa]

It might be worth dropping a line or contacting Ford on the number or email below. With the details and a screen shoot and ask them to assist.

Ford Customer Relationship Centre, UK
Phone: 0203 5644444
Email: ukcrc1@ford.com

My knowledge of engines is non existent so hopefully someone more knowledgeable will give some advice

Thanks, done this today. They ask a million questions...

[marshpa]

Although not easy a video/audio of the symptoms presented to your dealer would help your case.

I did! Along with screenshots from my Fordpass app. No luck!

[marshpa]

Air mass flow sensor faulty or failing?

Wouldn't that throw up a code?