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Ladies

Did an oil change on an rb25det, didn't run a flush though it and replaced oil etc. Car was driving fine and then all of a sudden it sounded like a wrx, started ticking and all the rest of it.

Firstly I thought it may have been a lifter that was sticky something getting jammed near it causing it to run on 5 cylinders. So I ran the nulon "lifter free" additive and that didn't change much.

Upon closer inspection I noticed the ticking was coming from the back, on the exhaust side. So I drove the car home and checked out the plugs and this is what I found.

You can see the white residue on the rocker cover and also on the side of where the packs would sit. No. 5 seems to be the issue here, as the pack has melted around the plug and the clip that it goes into has also melted.

img0147yn.jpg

img0148t.th.jpg

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img0151el.jpg

As I said before the ticking is coming from the exhaust side, could this be a faulty exhaust gasket? If so, how would I check it?

So basically I need second hand ones of everything in the photo, minus the plugs and the cover. If anyones got some that would be great!

If I fix this issue with working parts could there be another issue in cyl 5 / 6 that may have something to do with this?

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exhaust gasket will have nothing even remotely to do with it.

generally i've found oil additives are a waste of time. if theres a serious problem it will never be fixed by tipping a little something into the oil filler.

before you go replacing parts and just shoving them back on you might wana have a little investigation as to how it got so hot in there to melt the coil pack and loom like that. what plugs where you using?? my best guess as to the white crap everywhere could be porcelain off the plugs, as by the look of that plug it has been very very hot and the more i think about it the more i like that theory.

first things first you need to find out how the hell did cylinder number 5 get so freaking hot as to cause all that. thats obviously what caused the running on 5 cylinders and hence the engine sounding different

Edited by jonboy

actually after having thought a little more about it, sounds to me like you could have a broken valve, if its bent out of shape or something that could explain the excessive heat generated through the plug as well as the ticking noise as the valve wont sit properly on its seat.

do a compression test. if compression is way down on number 5 then thats almost certainly your problem.

if so, time for the head to come off

Edited by jonboy

Don't know what burnt your gear but the ticking is quite normally for a cylinder that isn't igniting...just have a quick look at the top of the piston and the spark plug thread. Replace coilpack / spark plug and probably that loom. It looks like something shorted or didn't have a good earth? Never seen something like this before...it's almost like the spark plug came loose and the combustion started breaching the cylinder bore with exhaust/flame? Very queer.

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