I was doing around 60mph and then I heard a pop and lost all power. When I pulled over, my car was 'mis-firing' and sounded like it was going to blow up!
When I looked under the bonnet, one of the HT leads was hanging out. Also the spark plug had flew out!!
After putting the spark plug back in and connecting the HT lead I managed to get my motor home. However, it still isn't right. When idle and in low revs its still 'missing' and 'mis-firing'.
Would a new set of plugs fix this problem or could there be something else wrong?
The first thing to work out is why the plug had come out, was it not tight enough or has the thread in the head failed? Next thing to try is a new set of plugs as you may has a duff plug, then try a new set of leads. On the other hand fined a garage who has a diagnostic snap-on box or a like and get them to run a test. I had a miss fire went to my local garage who ran a test, result was a failing plug lead!
My new Spark Plugs arrived today and I 'attempted' to fit them.
I say attempted because the plug in the 2nd cylinder would not tighten up!!! :-(
Does this mean that the thread on the cylinder head has gone??
If so, how big of a job is it to get sorted??
One of my mates said rethreading would cost £50-£100 without taking the head off, another friend said it would cost £££s because they would need to take the head off.
sounds like the thread has stripped in the head,you may be able to get a "helicoil insert" put into the head in situ and then refit a plug -if not its head off ,that being the case I would simply replace the head as helicoil inserts are never a strong as the original and can fail when changing plugs ,and there a still cheap new cylinder heads around for the time being.
I also want to mention that thread repairs are typically stronger than the original threads. Many years ago I worked in a skating rink and we repaired skates with heli-coils all the time. Not once did the repaired ones ever strip out again.
So, get her repaired and you should be good to go.
Last edited by DaFlake; Jan 6th, 2008 at 11:56 AM.
I have had a helicoil fitted today and the car is running again
However, sometimes the car is still missing a little bit - when ticking over and when changing gear. Also when I took the car to around 4,000rpm it was juddering and then I got my power again.
Could this just be a case of giving it a few miles to try and sort itself out or could it be something else?
It does not do this all of the time, only when I have just started the car (hot or cold).
Well my MCS has about 40k on the clock so maybe I should change them.
Should i just get original leads or shall I upgrade to something a bit better (bearing in mind I am running around 215bhp). If so, which are recommended and where to buy?
Yes, may could even be the cause of the intial problem if they were buggered, I would have changed them anyway just to be sure it's not like they are expensive...
When talking fails, it's time for violence. ~ batou.
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Problem with Spark Plugs... 
