How To Test Spark Plugs And Ignition Coils

[BigMo82]

I have had a idle problem and the mechanic suggested it could be a failing ignition coil. Just trying to work out the best way to test spark plugs and ignition coils. I removed the sparks yesterday and have attached a photo. Could someone kindly advise if these look normal? There was a little oil on the threads but none on the tips. They were put in about 2200 miles ago. Also I put the coils and sparks back in different order and the idle has got worse. Does having a bad coil or spark have more or less effect depending on which number cylinder they are in?

I have got a sealy ignition coil tester but it didn't come with any instructions. Not sure if I have to remove all coils when testing or if I should remove the fuel pump fuse.

As always any help is appreciated.

Mo

[gazza1286]

Instructions can be downloaded here:

https://www.google.co.uk/#sclient=tablet-gws&q=Sealey+spark+plugs+ignition+tester+instructions&oq=Sealey+spark+plugs+ignition+tester+instructions&gs_l=tablet-gws.3...37606.37606.1.41166.1.1.0.0.0.0.118.118.0j1.1.0...0.0...1c.1.15.tablet-gws-psy.2vlvncBC3ek&pbx=1&bav=on.2,or.r_cp.&fp=72d70540f857aa8&biw=800&bih=

The plugs look fine to me.

[BigMo82]

Thanks for the reply Gazza. Any ideas where the fuel pump fuse is?

Mo

[SAM LOVERS HER TOYOTAS]

HI

Yup those sparks look fine to me too...that little bit of oil on your sparks that you noticed...I believe its your rocker gasket that will eventually need replacing but is fine as it is for now...I have the same issue with my 2006 1.6 Corolla...bought the gasket months ago...still in my boot though lol!

[Druid Boy]

Plugs look fine. there is always oil on the threads (I don't know where it comes from) so don't bother replacing any more gaskets etc. Check the gap on the plugs though, they look a little big to me.

[BigMo82]

Thanks for the replies. I didn't adjust the gaps on the spark plugs as I was told and have read that these Iridium plugs are already adjusted. I could be wrong though, do the adjustments make a big difference? Still trying to get this damn idle problem sorted. It's getting me to the point where I hate having to drive it.

Mo

[Druid Boy]

To be honest I'm not 100% sure but I always check the gap, just cos its easy and they are off sometimes -especially if they been bumped or dropped in the shop.