Ford Fiesta Zetec 1.25 (W ) registered - Ford Fiesta Spark Plug Gap Setting,Opinions Please

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Wed 4 Jul 2012 20:04
Ford Fiesta Zetec 1.25 (W ) registered - Ford Fiesta Spark Plug Gap Setting,Opinions Please - KenC

My wife has very low mileage Fiesta 1.25 Zeetec. Owned for 2 years,It was purchased from a local car dealer who serviced it before purchase. New spark plugs were fitted at the service.

After 2 years and only 4,000 miles I decieded to check the spark plug gaps, the owners manual states spark plug type AYFS 22C gap 1.3mm

The Spark plugs gaps were set at 40 thou, I calculated 1.3mm as 50 thou which did appear to be a large gap..........but I reset them all to 50.

After 2 tankfulls of fuel I suspect the MPG has dropped by 10%

Are there any ford mechanics that can advise me please ? should I leave them at 50 or reset them to a smaller gap ?? thank you

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Thu 5 Jul 2012 11:12
Ford Fiesta Zetec 1.25 (W ) registered - Ford Fiesta Spark Plug Gap Setting,Opinions Please - Dabooka
I can't (and wouldn't) state for certain about your engine, but I do know that the 2.0 Zetec blocks didn't like Champion plugs too well and most people set them smaller than the 1.3mm stated (usually about 1.1 if memory serves).

TBH honets if you thought it was running better before hand, I'd put them back to .040
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Thu 5 Jul 2012 11:58
Ford Fiesta Zetec 1.25 (W ) registered - Ford Fiesta Spark Plug Gap Setting,Opinions Please - unthrottled

My parents ran a 1.6 Zetec and the recommended gap was 50 thou. Puts too much strain on the coils-and, sure enough, one burned out and took the cat with it.

Basically, set the gap as small as will give a stable idle. There's nothing to be gained by a larger than necessary spark plug gap.

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Thu 5 Jul 2012 15:57
Ford Fiesta Zetec 1.25 (W ) registered - Ford Fiesta Spark Plug Gap Setting,Opinions Please - KenC

thank you for your reply, thats interesting

I wonder if FORD have ever issued any advice on this, I,ve not been able to find any via google. Do you know how many miles your parents car did with the plugs at 50 before

problems were experienced ?

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Thu 5 Jul 2012 16:12
Ford Fiesta Zetec 1.25 (W ) registered - Ford Fiesta Spark Plug Gap Setting,Opinions Please - Dabooka

I think it was common on a lot of Fords at that time, too big a gap used to burn out plugs and HT leads, especailly cheaper non-OEM sets; it was (is) common practice to reduce the gap as a consequence.

I'm suprised Google throws nothing up.

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Thu 5 Jul 2012 16:46
Ford Fiesta Zetec 1.25 (W ) registered - Ford Fiesta Spark Plug Gap Setting,Opinions Please - unthrottled

90K/7 years if I remember correctly. Not terrible durability to be fair. Unfortunately, they drove it home without disconnecting the relevant injector and that overheated the cat.

I run 30-35 thou and my coil packs have never broken down. Tis an 8 valver though, 16V engines often need a slightly larger gap. .

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Tue 10 Jul 2012 13:49
Ford Fiesta Zetec 1.25 (W ) registered - Ford Fiesta Spark Plug Gap Setting,Opinions Please - KenC

I will be taking the advice given here and reducing the spark plug gap,can anyone who knows or has a Ford Fiesta workshop manual advise me of the recommended torque figure for tightening the spark plugs ( I have a torque wrench so may as well use it)

thank you

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Fri 20 Jul 2012 16:05
Ford Fiesta Zetec 1.25 (W ) registered - Ford Fiesta Spark Plug Gap Setting,Opinions Please - Galaxy
Ford changed the recommended gap for the Zetec engine to 1.0mm. Previously it was 1.3mm but it was changed due to too many failures of HT leads and coils.

If you buy the right plugs they are already set to the correct gap. I myself always use either genuine Ford or NGK.

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Sat 21 Jul 2012 08:53
Ford Fiesta Zetec 1.25 (W ) registered - Ford Fiesta Spark Plug Gap Setting,Opinions Please - KenC

thank you for your message, I have already re set the gap to 40th, the car does seem to run a little smoother.

I do not have a workshop manual, do you happen to know the torque settings for retightening the spark plugs ?

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Sat 21 Jul 2012 11:36
Ford Fiesta Zetec 1.25 (W ) registered - Ford Fiesta Spark Plug Gap Setting,Opinions Please - jc2

Recalculate!!! 1.3mm. is nothing like 50 thou. or even 40!

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Sat 21 Jul 2012 11:45
Ford Fiesta Zetec 1.25 (W ) registered - Ford Fiesta Spark Plug Gap Setting,Opinions Please - jc2

Ignore above post!!

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Sat 21 Jul 2012 12:33
Ford Fiesta Zetec 1.25 (W ) registered - Ford Fiesta Spark Plug Gap Setting,Opinions Please - Ben 10
If you buy the plugs from Ford parts dept. the gap is pre set.
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Sat 21 Jul 2012 13:47
Ford Fiesta Zetec 1.25 (W ) registered - Ford Fiesta Spark Plug Gap Setting,Opinions Please - KenC

Thank You for the suggestion Ben, I have almost new plugs that were set according to the car handbook at 50 ( to large) now thanks to earlier contributions they are at the correct gap (40)

All I need is the torque settings so I don,t overtighten them, so if anyone can tell me that will be great !

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Mon 23 Jul 2012 11:03
Ford Fiesta Zetec 1.25 (W ) registered - Ford Fiesta Spark Plug Gap Setting,Opinions Please - Galaxy
The torque settings for the spark plugs is 11 lbf ft (15Nm)

These figures I have given are taken from the Haynes Ford Mondeo manual, which also uses the Zetec engine. I don't have a manual for a Fiesta but don't see what the figures given would be any different for that vehicle.

I myself always insert the plugs and tighten by hand only. I hold the socket extension in my hand and turn very slowly, feeeling for any possible signs of cross-threading. You must take the greatest care that they are not cross-threaded, this is very important.

Finally, when the plug is as tight as it possibly can be I then attach the rachet handle to the socket extension and just very lightly "nip" the plug up to fully tighten it. The Haynes manual suggests a figure of not turning the plug more than 1/16 of a turn for final tightening. In practice I have found this figure to be about right and have never had any problems with either stripped threads or subsequently removing the spark plugs at a later date.

Of course, if you happen to have a torque wrench which goes down to the very low figure quoted then using that will also be fine!
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Fri 27 Jul 2012 03:32
Ford Fiesta Zetec 1.25 (W ) registered - Ford Fiesta Spark Plug Gap Setting,Opinions Please - 1litregolfeater

I wonder if Ford were up to, how shall we put it, " engineering solutions?" "creative engineering" sound better?

What I mean is, it sounds like an awfully big gap for a shopping car's meagre electrics to cope with.

Now, if Ford could get them coming back to get fixed, they could make more money.

Not suggesting a conspiracy or anything like this ever happens in our capitalist heaven on earth, but it makes you think.

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Fri 27 Jul 2012 13:29
Ford Fiesta Zetec 1.25 (W ) registered - Ford Fiesta Spark Plug Gap Setting,Opinions Please - unthrottled

The conspiracy theory falls flat when you consider that the damage to the brand far outweighs any additional revenue from fixing ignition systems. The 1.3mm gap was simply a bodge to pass the emissions standards of the day. A bigger gap does help at idle/overrun conditions.

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Thu 9 Aug 2012 02:33
Ford Fiesta Zetec 1.25 (W ) registered - Ford Fiesta Spark Plug Gap Setting,Opinions Please - 1litregolfeater

ah I see, some very clever men work there. If Skoda had done this, we could still have the Estelle.

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