Spark plug / coil issue - hole full of dust - NC1

Technical Area Engine, Transmission, Exhaust etc
1
  1. My model of MX-5 is: NC1 2006 2.0l Sport
  2. I’m based near: Birmingham
  3. I’m looking for technical help or recommendations on: Spark plug / coil issue

Hello everyone,

Looking for a bit of advice, I have a 2006 2.0 Sport, 95k miles. I suspect it has been neglected a little before I picked it up last year.

I’m working my way through the service jobs, and was going to change the spark plugs today. When I removed the coil pack from the front cylinder, the hole is full of dust, and I can’t even get the socket onto the old plug. Clearly I don’t want to remove it until the dust is gone, as I don’t want the dust in the engine. I’ll try the vacuum on it next week (ran out of time today, I thought it would be a simple job).

The question for the assembled wisdom here - any idea what has caused it? If it’s the coil, does this mean it’s on the way out? Or are there some seals that are may have failed allowing this to accumulate over time (the engine bay was quite dusty when I got it, and I’m guessing that the plugs have not been out for a while).

The engine has been running fine, I’m only changing the plugs as I don’t think they will have been done for a while.

Any thoughts anyone please?

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2

Yep thats pretty dirty.
I had a coil pack fail on my other halfs Vauxhall Adam, the end of coil pack was discoloured and covered in crud. However it was green ? Same on the top of the plug.

3

Looks like rust deposits to me. I wonder if the spark plug well has been full of water at some point causing the metal part of the spark plug to rust. My concern would be that the plug has rusted into the head, once you’ve cleaned it out, take care removing it, you don’t want a broken plug stuck in the head!

4 Likes
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Thank you for the advice @Roadster_Robbie . i’ve cleaned out today and took my time extracting the offending plug. The others were not so bad, just that one. I 've changed the whole set today.

These have certainly seen better days!

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1 Like
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Bet they’ve been in the 95k miles. Should be changed around 64k ish.:+1: