2HondaDave

A couple of months ago my check engine light came on, after the car had been running for quite a while. Diagnosis showed the codes were misfire on cylinders 1 and 3. After my garage had reset the codes and serviced the car the light went out an all was well for a couple of weeks. Next time I was going for more than about 2 hours it came on again. Same codes.

I took the spark plugs out and found that number 1 was a bit fouled and number 3 was actually broken, the tip where the coil makes contact with the plug was broken in two, so it was surprising that it actually went as well as it did. Bought a set of Champion plugs from Halfords (fitment for the S2000 was shown on the packaging) and popped them in and all was well.... until this morning!

After a brief stop on my way to work for coffee I felt a slight hesitation, shortly followed by a flashing CEL. Pulled over and turned it off with it still appearing to be running fine. Turned it back on again, flashing CEL again and a bad misfire, running on 3 cylinders. The RAC man said that he'd never been called to an S before :-) After he'd spent about 20 mins trying to get a response through the diagnostic port he took the cover off and extracted the first coil pack. The black plastic cap was broken and it was really hard to get it out. Once it came out it showed why as the coil was really mangled with the bottom broken and wires hanging out of it. The spark plug was lifted out, also badly mangled and melted. The threads on the plug were mangled. It appears that the plug has been forced out of the head, impacting and making a mess of the coil.

I guess, other than getting it off my chest, I'm wondering if there are any known issues with these plugs? I'm worried that I didn't have them tightened up properly or something causing this to happen, but surely it would have shown itself before now, I've done several thousand miles since I put them in and it's been running as well as ever.

My usual garage are having a look at it hopefully this afternoon and we'll see what damage there is to the head. I'm hoping it's minimal or that it can be repaired. Anyone else experienced something like this? Anything I should be looking out for or aware of?

First time I've ever been let down by the car :-( Had it 10 years and 80k miles now.

unclefester

Plugs not tight enough to start with ..... now you wonder what has made it past the plug into the head so i'd guess it will be head off for some inspection.
Based on what happened to PaulF .... you might want to get them to inspect the head for damage.

2HondaDave

OK, thanks UF, that's exactly the kind of advice I was after. Guess this is going to be fairly costly in labour alone...

2HondaDave

... guess I better start making alternative arrangements for getting to work for a while then. My wife is going to give me the "you should sell that old car and buy a nicer, newer one!", again

unclefester

It might be nothing more than a cleanup and refit job but if anything has made it past the plug, dropping the oil and looking for anything that is missing from what you pulled out would be good.

https://www.s2ki.com/s2000/topic/104...p-end-failure/

Might be worth having a read of that. I'm NOT scaremongering as that's worst case scenario i think.

2HondaDave

The threads on the broken plug look pretty bad, so I've asked them to look at the corresponding ones on the head as a starter... My coil and plug don't look anywhere near as bad as PaulF's, but it would certainly appear to be a similar root cause.

Definitely will get them to check for debris too. Fingers crossed.

If the threads on the head are knackered then either helocoil it or a replacement head I guess assuming nothing is amiss further down.

Thanks for the replies

mattg4321

I wouldn't fit Champion plugs again in future.

Most of us stick to the specified NGK plugs.

Burnsy

Sorry to hear this pal.

Don't want to scare you too much either but this sounds like exactly what happened to mine, and unfortunately mine ended up needing a new engine!

Feel free to have a read (pics included) Engine Thread

2HondaDave

That was my intention, but they were all I could get a hold of in a hurry

2HondaDave

That's one of the things I fear. However I don't think mine was quite as catastrophic as yours from the pictures and what I've seen so far of mine. The old coil and plug came out ok, there is no sign of any debris below so far, and I could see the top of the piston down the tube and it looked unmarked. Also the engine was still able to run rather than just stopping like yours. Fingers crossed.

I've actually been dithering over replacing the car for something more practical for quite a while, now that we have 2 kids and I'm working 125 miles away from home (not that I'm doing that every day). I had decided to just keep it permanently, put some new seats and interior in and bought a new stereo (was going to fit that this weekend), and now this

Once my garage have had a chance to look at it more closely I will have a better idea of what's going on. Either way it's going to need fixing. First up I need to know how bad it is and how long it'll take to repair so I can sort out alternative transport, I can only work from home for so long and don't fancy commuting on my Harley at this time of year for too long!!