I've been doing some basic maintenance on my 190,000km Focus 1.0L 125PS. I'm an experienced bicycle mechanic and generally good with fixing 'stuff', but this is the first time I've done any significant work on a car. No disasters so far, thankfully. Anyway, having just changed the spark plugs, I was hoping someone could give me an opinion on the state of the old ones. I don't know when they were last changed. Car ran fine before I changed them, but I was quite surprised at how crusty the external bits of the plugs were, but maybe that's not a problem. There are some white deposits on the sparking parts of the old plugs, possibly not visible in the photo. 

Cheers

 

The plugs look a little black and sooty, if they went that way quickly it would indicate over rich fuel to air ratio, but from the corrosion on them - and the typical lack of servicing vehicles get - I'd say they've probably been in years. Air filter worth checking, that's for sure.

When I change plugs I put a spot of copaslip grease on the threads, if they are prone to corrosion on that particular vehicle a spot of lithium grease on the ceramic end would help. I'd clean up the plug leads - any old rag and a bit of white spirit tends to do the job.

Well done for giving it a go, you're learning alll the time.

Thanks for your reply. I did the air filter as well, and cleaned up the leads before putting it all back together.