Ford Focus II 1.6, 2005 - Spark Plug thread size

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Sun 25 Mar 2018 20:12
Ford Focus II 1.6, 2005 - Spark Plug thread size - deanep
I have recently tried to replace spark plugs and find that all plugs listed by on-line suppliers for my car have a 14mm dia. thread which just fall into the existing plug hole. The old plug is marked NGK TR 5A-10 and I have measured it as having thread diameter 15mm approx. and is also visibly larger diameter.
Strangely, when I look up technical details of a NGK TR 5A-10 plug on-line it seems to be specified as being suitable for my car, and is stated to be 14mm thread ! So why is the Plug removed from my car at least 1mm larger than 14mm and yet identified as NGK TR 5A-10 ? And where can I be sure to get the right plug ?
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Sun 25 Mar 2018 21:40
Ford Focus II 1.6, 2005 - Spark Plug thread size - Chris Miller

Ford dealer perhaps?

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Mon 26 Mar 2018 14:53
Ford Focus II 1.6, 2005 - Spark Plug thread size - 2010Jagman

Are all the plugs the larger size? had it before that a car had been helicoiled after a stripped thread and it came out with the plug instead of staying in the head

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Tue 27 Mar 2018 20:47
Ford Focus II 1.6, 2005 - Spark Plug thread size - focussed

NGK listing for this car is TR5B - 13

!4 mm dia x 17.5 long thread - conical seat - stock no 4559.

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Wed 28 Mar 2018 16:31
Ford Focus II 1.6, 2005 - Spark Plug thread size - galileo

Are all the plugs the larger size? had it before that a car had been helicoiled after a stripped thread and it came out with the plug instead of staying in the head

Good thinking, Jagman, I think you have the answer, the OP needs someone to re-helicoil the plug hole. As a temporary fix screw the old plug back in.

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