Misfire until plugs changed

[m44t-xx]

Hi guys,


So this is on my rb25 S14a. When I last used it before the winter I noticed it had developed a misfire, sounded like 1 cylinder wasn't really happening a long with a small amount of blue smoke, however the car has been used much since replacing the dead turbo so that could have a part of play.

So yesterday I had a spare hour, changing the plugs, boom, back to normal. Now I wasn't paying a huge amount of attention but 1 plug definitely had oil on the threads and all smelt of fuel (it is waiting for a map adjustment so could be slightly over fuelling)

So this has got me thinking, is this likely to be the valve guides that have possibly let oil in? How do I test it?

And finally on an RB what's it likely to cost to fix, I will have to pay someone as am now changing jobs so have no time, and limited knowledge in that respect.


I will also do a compression test at some point for piece of mind.

Any help is appreciated,


Cheers

Mat

[VIDAL BABBOON]

What plugs were they ? Denso are known to break down and fail.

Also was there any oil in the spark plug port or just on the threads that were within the cylinder ?

If none in the port and only within the cylinder then you either have baggy valve guides that have in turn damaged the valve stem oil seals or just worn valve stem oil seals.

[m44t-xx]

I think they were NGK plugs, however i will have to check. The car clearly has had a leaky rocker gasket in the past which hasn't helped. I am going to hopefully spend some time looking at it soon.

Is it the valve stem oil seals. How much would they cost to get done? Also what's involved?

[VIDAL BABBOON]

Is it the valve stem oil seals. How much would they cost to get done? Also what's involved?

If they are the guilty party then its a little involved but not head off involved.

If you are not a competent spanner twirler, then its something to get assistance with or provide bacon butties and coffee to someone to do for you lol