WHYI had a misfire on cylinder 3, diagnosed when I went on Awesome's rolling road. Spark plugs hadn't been changed for 18k miles or so so i thought it couldn't do any harm. Awesome also suggest that any tuned car runs the colder spark plugs. They even fitted them to a brand new Stage 1 Golf R which was misfiring and it cured it (apparently anyway).
WHICH ARE THE RIGHT PLUGS FOR MY CAR?I was reading from the NGK website about heat gradings. They say that for every 75 - 100 bhp increase you should go a step colder. That being said the old standard heat range was six for a 2.0 tfsi. Based on that the 7s would be good for upto 300bhp and anything over 300bhp the 8s. I have 8s and have about circa 260 to 270bhp. I do lots of short runs now I have moved so i am thinking of switching back to the 7s. As the plugs will never reach the 450c temp it needs to burn of the carbon and I very rarely do long high speed runs and no track driving. I have copied a link to the article I was reading.
http://www.ngksparkplugs.com/techinfo/spark_plugs/installation.asp
SOURCINGInitially I was going to take advantage of Awesome's offer of 4x spark plugs for £32 delivered, but with the kind help of Jaywoo-GTI i was directed towards this eBay listing:
http://www.ebay.co.uk/itm/320797953741?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649Items delivered quickly and safely wrapped, and for £10 less than Awesome: awesome! (Or not, as the case may be
)
FITTINGhttp://www.golfmkv.net/blog/archives/9#i didn't have the tools (was short an extension for my socket set), so popped it down to National Tyres in Newcastle-u-Lyme where Richard quoted me around £10 to do it for me, but he couldn't do it there and then because of bookings. Instead he offered to lend me his tools so I could do it myself.
Got the coils off, at which point i noticed one of my coils (cyl 4, not the one misfiring) was rusty despite being changed less than 3 months ago under the recall:
(Advice welcome about that^.) I went inside to ask Richard's advice, at which point he came out to the car and, without me asking, changed the spark plugs for me. When I asked him how much, he said "nothing". Result!
OTHER VERSIONSOEM
Nology
??? (feel free to add others, i didn't really research it tbh)
PLUS POINTS1. Cost - OEM plugs are in the region of £45 to buy. These were half the price, and from some of the posts on VAGOC it looks like VAG main dealers sometimes use the NGKs anyway (?!)
2. Misfire gone (!) - so they served their original purpose
3. Increase in fuel economy? - seems that way. On my regular trip to the gym which is 16mi away (don't ask) i got better fuel economy than normal, despite the fact that it was 2deg and my car really seems to suffer in the cold. I was driving like a bit of a prat too, and even stopped off for some V-Power on the way which always hurts my fuel economy average on the DIS.
4. Smoothness? - oh how subjective this is, but the car just feels better.
MINUS POINTSNONE!!! If your car isn't tuned apparently colder plugs don't get hot enough to burn away deposits and you can get fouling of your plugs. I'll be going Stage 2 soon hopefully, so still happy with the purchase. I'll keep you informed if I run into trouble.
15/3/12 Update - roughly 6k miles on standard tune with no degradation in performance
28/8/12 Update - roughly 12k miles on standard tune. Single episode of misfire 2 months ago. Disappeared with no recurrence. No fault codes logged, no problems with cold starting.
14/10/13 Update - roughly 20k miles on standard tune. No further episodes of misfiring. The plugs were changed for Nology plugs as part of a major service and does feel a little more responsive. I maintain that for a routine plug change they are good value and should not be considered an upgrade - at least not on an unmapped K03 car.
SUMMARYFor £21.32 fitted (not including the petrol it took me to drive to the garage) I'd say this is a right old result. Whether or not they make a difference is irrelevant, they're half the price of OEM and do exactly the same job. If they're better that's just an added bonus.