Hi, I need some advice. In the Ford fiesta 1.4/BIFUEL/2014 car, I changed the spark plugs with new ngk iridium ones ... https://www.amazon.de/-/en/ILTR6H8G-NGK-96870-Spark-Plug/dp/ B006DI3ZSM. After installing them, the engine did not work very well, I disassembled them again and they were half smoked, while the old ones were clean and at best they were identical to the new ones. However, I left the new ones on the car and after some time the engine recovered and works normally. My dilemma is that I can't find exactly what distance the spark plugs should be, taking into account that they work more on LPG than on gasoline. This type of spark plug has a distance of 1.2 mm and other types of spark plugs compatible with the engine on the car have a distance of 0.9 or 1 mm. I am also looking for a set of plugs with resistance as close as possible to 6k per meter, obviously I only found fakes with resistance higher than 10k per meter. Of the dozens of sites searched on the Internet, none posted the resistance of the sheets. If someone knows more precisely what is the exact distance of the electrodes for this engine, please post it. Thanks!

@JW1982 Should be able to tell exactly what gap you need.  

You should, but unfortunately it doesn't say anywhere, at least I can't find it, that's why I'm asking, maybe someone has encountered this problem!

 

They're most likely to be preset. You should be able to look them up for your car on the NGK website and it will tell you there.

Did your car come with LPG from the factory?

I believe the LPG was a non UK option...

https://www.automaniac.org/compare/5539/8851/ford-fiesta-1.4-lpg-VS-opel-corsa-1.2-bi-fuel

For some reason, they never gained the popularity here that they have in Europe, though goodness knows why as after owning an LPG car, they are brilliant!

11 minutes ago, Zalmoxiss said:

You should, but unfortunately it doesn't say anywhere, at least I can't find it, that's why I'm asking, maybe someone has encountered this problem!

 

Think that got slightly lost in translation.  The member I tagged is good with spark plug figures, hopefully he'll see this.  

I just looked them up on the NGK website for another country and they are the correct plugs and the gap is preset to 0.8mm.

Here's a breakdown of the part number...

Thanks again TomsFocus you right. I wasn't careful with the translation in my language, I hope that @JW1982 sees this post and tells us the exact gap of the spark plugs, although @#Frembrit showed clearly enough that the gap is 0.8mm. I kept the old spark plugs and I measured them with a ruler and it shows me 3 pieces of 0.7 mm and one 0.4, this last one is definitely decalibrated and it seems that I did well to change them. However, it is curious that the new ones have a 1.2 mm gap, or so I think I saw correctly because I didn't have the measuring tape purchased at the time and I measured with a tape measure. I may be wrong, but I will soon take apart a spark plug and measure it correctly. In principle, now I am clear and I hope that those who will read the topic will also, so the factory preset gap according to the picture above is 0.8. Thanks to all!

This is the correct spark plug gap for the 1.4 Sigma Bi-Fuel engine as specified by Ford:

Note that the prescribed spark plug gap for the regular petrol version of the regular 1.4 Sigma engine is 1.2 mm.

Ford specifies the following spark plugs for the Fiesta MK7/MK7.5 1.4 Sigma engine:

1.4 Sigma Petrol engine
Finis number 1787829
Part number 4M5G-12405-AA
NGK equivalent TR5B-13 --> pre-gapped at 1.3 mm, must be adjusted to 1.2 mm.

1.4 Sigma Bi-Fuel engine
Finis number 1680032
Part number 9A6G-12405-BA
NGK equivalent ILTR6H8G --> pre-gapped at 0.8 mm, must be adjusted to 0.7 mm.

 

It seems that you have the wrong spark plugs.

@JW1982 you are a lord, and a big thank you for taking the time to answer me. In other words (if I understood correctly), I stay with the current spark plugs, but they must be adjusted to 0.7 from 0.8 mm. Thanks again!