Read on a forum a  ford focus had problem with rough idle after a service, then was informed could be spark plug problem,not by garage on the forum and that the ford focus can act up with non ford spark plugs  on taking car back to garage  turned out to be spark plug fault,  just want to know any truth to this , can they have problems with non ford spark plugs?

2 hours ago, scoop64 said:

Read on a forum a  ford focus had problem with rough idle after a service, then was informed could be spark plug problem,not by garage on the forum and that the ford focus can act up with non ford spark plugs  on taking car back to garage  turned out to be spark plug fault,  just want to know any truth to this , can they have problems with non ford spark plugs?

never had a problem with other brand spark plugs when i had a petrol focus many yrs ago. ngk, bosch all fine. did the garage set the plug gap correct 

1 minute ago, andypsp said:

never had a problem with other brand spark plugs when i had a petrol focus many yrs ago. ngk, bosch all fine. did the garage set the plug gap correct 

don't know , but replacing plugs was the answer, i have never used originals on any car never had any problems, but read this wondered if anyone ever had problems with focus.

 

2 minutes ago, scoop64 said:

don't know , but replacing plugs was the answer, i have never used originals on any car never had any problems, but read this wondered if anyone ever had problems with focus.

what brand did the garage put in for you then ?

16 minutes ago, andypsp said:

what brand did the garage put in for you then ?

No,wasnt me, read on another forum, one reply was ford focus don't like after market spark plugs only original ford and predicted spark plug could be the cause of rough idle, turned out he was right, another set put in, ford ones? dont know.

there are a LOT of fake Chinese trash spark plugs out there these days.  Allegedly a lot of fake NGK ones where the electrode falls off....

one small benefit of being ripped off by your local ford dealer, it should mean you get genuinely average parts.  That said the iridium NGK ones I got off ebay are fine 30k on

https://www.ebay.co.uk/itm/4x-NGK-LTR5IX-11-4344-IRIDIUM-IX-SPARK-PLUGS-MAZDA-5-CR19-2-0-03-05-UPGRADE/153125024150?hash=item23a6f67196:g:58oAAOSwAopbWtzW:rk:39:pf:0

Features:

 

• 0.6mm fine Iridium centre electrode tip ensures high durability while providing a consistently stable spark.
• Zinc-chromate plating provides superior anti-corrosion and anti-seizing properties (do not apply thread lubricant - read installation section below).
• Improved acceleration and better fuel efficiency.
• Ultimate design from the result from years of extensive research and development.
• Manufactured using the most advanced laser welding technology available.
• Tapered ground electrode improves flame expansion from the spark due to as minimum obstruction as possible.
• Longer lifetime than standard spark plugs - Up to 50,000 miles.
• Improves idling stability & throttle response.
• Spark gap remains virtually unchanged throughout the entire lifetime.
• Easier engine starts - Great for freezing winter mornings.
• Superior anti-fouling
• Lower required spark voltage
• Outstanding quality as you come to expect from NGK.
• Proven track record and used in millions of vehicles around the world.