Hi

Have an X Reg Fabia MPi and plan to do an oil/filter change real soon. I'm also planning on changing the spark plugs as we haven't done this since buying the car. Obviously, I can't be 100% sure they have ever been removed..

Having never changed the plugs on a Fabia before, I thought I'd ask advice before proceeding..

Firstly, are there any brands/types of plugs that are recommended? Any brands/types to avoid?

Secondly, any potential 'gotchas'? Is access easy? Do they come out easily or are they prone to rusting in place? Do the cylinder head threads strip easily?

Oh, one other thing, what sort of oil for the oil change? Any benefit in using the expensive stuff or just use the basic stuff?

Bosch Super 4 FR78 should work ok (I think FR78X have the bigger gap and are therefore not suitable). I don't think you'll have any issues, the coil pack comes off easy and goes back on easy. Just ensure you don't misthread the new ones, this can be done easily with care by hand.

I don't have the 1.4 mpi so can't comment on the location of the plugs, but without the DOHC, they are probably easier than most to get at (the plugs on the 1.4 16v are very recessed!). I've used Bosch Super4 plugs for a number of years - slightly dearer at around £20/set but I think they do help the performance a little and last longer. Not completely sure they are compatible with the 1.4 mpi engine though, you'd need to check up on that. I also put a little bit of copper slip on the threads of the new plugs to help avoid future problems. Good luck.

I am pretty certain the Halfords catalogue thing directs you towards the FR78X plugs for the Fabia, I am also pretty sure this is wrong and the correct ones are FR78. One thing for certain is that Skoda say the gap should be 0.8mm on the 1.4 8v mpi, so that's the key thing to look out for. I believe FR78 has the 0.8mm gap (the gaps are referred to in the Halfords catalogue and I think Halfords get this wrong hence recommending wrong plugs). These are the ones I currently use anyway and no obvious problems so far.

The original plugs have Skoda logos on. If it's gone over 40k and on the original plugs, the gap on them will be noticeably over 1mm (due to wear). My ECU registered an intermittent misfire on one of the cylinders on original spark plugs at about 48k miles.

Ive changed them on a 16v.. was really hard to unscrew using the spark plug removal tool.. invest in some handy wd40 if you have this problem.. screwing new ones in was very simple though.. just keep in mind to not cross thread!

I changed my plugs recently on my 1.2.. I used NGK the gap was present but checked them with my feeler gauge any way... i think it was 1mm but im un sure what it is for the 1.4mpi version.. check the haynes manual...

when i changed mine i used a tin of dust off ( compressed air) to get the crap away from the plugs b4 loosening them... Dont want nasty bits of rust n dead flies to fall in there...... on relocation i used a 30cm length of garden hose pipe .. slipped it onto the bit the sticks out and manovered it into position and was able to start screwing it a bit in too... and if u start of on the wrong thread the hose pipe will slip and not cause any damage to the thread...

I checked the gap of my old plugs and they were at least 2mm ... not due to poor setting but being burnt away... have noticed a good difference in my fuel ecomony too after changing... along with oil change

Edited 17 May, 201016 yr by mudyf0x

Great advice, guys, thank you very much.

One last question, is there any real advantage to the modern four pronged plugs over the more conventional plug with a single side prong?

To be honest I think there's very little advantage other than increased life expectancy. The spark always takes the shortest path, so one electrode wears down, then another, then another, so you have 4 electrodes to wear over time instead of one. You still get just the one spark, and I think claims of improved fuel economy and performance are probably somewhat over-egged.