Has Subaru Service killed my car?

Gremlins · Post by **Gremlins** » Fri Feb 11, 2011 12:48 pm

Hi,

Just after thoughts on this, but I recently had my MY06 2.0i Impreza serviced and included in this was replacement of the spark plugs.

Last night going home, the car lost power and it was immediately evident it wasn't firing on 1 cylinder. Quick check under the bonnet and the spark lead on the front passenger side cylinder was nearly all the way out of it's hole that goes down to the head from the cam cover.. Bit weird that it was so far out, but didn't think much of it and re-connected it. After restarting the car, the lead litterally "popped" straight out of it's hole and nearly all the way out again - that explained how it got so far out in the first place.

To me it looks like it's leaking compression pressure into the spark plug tube that goes down to the head from the cam cover, the end of the lead where it connects to the plug is also completely burnt and stuffed.

The only scenario I can think of at the moment is the plug has been cross threaded when it was installed and is not screwed all the way home. It's run for a couple of hunded k's and now started leaking. I was thinking maybe the plug has failed but I've got my doubts on that one because the lead sits high when it's clipped onto the plug compared to the one next to it and the only way I can think of that happening is if the plug isn't screwed in fully.

Anway, it's down at the Subaru service centre at the moment, will be interesting to see their spin on things, but if the plug is cross threaded what are the options for a proper repair? My guess is if the plug isn't screwed all the way home they'll just fit another one and screw it in via the remaining good thread and say it's fixed, but I'm doubtful about the long term reliability of this.

littlewhiteute · Post by **littlewhiteute** » Fri Feb 11, 2011 12:59 pm

Have seen spark plugs come undone before if they weren't done up correctly in the first place.

Your engine has leads? I thought you would have separate coil over spark plug?

Gremlins · Post by **Gremlins** » Fri Feb 11, 2011 1:14 pm

Yeah, thought about not being done up properly but I couldn't get in there properly to verify this as the spark tubes are very narrow and I don't have a suitable tool to get down there. Just feeling through the lead though and it feels like it's locking onto something solid and not a plug that's rattling around loose down there.

The engine is the standard single overhead cam N/A EJ20, not the twin cam 2.0R or Turbo. so not coil packs over the plugs.

littlewhiteute · Post by **littlewhiteute** » Fri Feb 11, 2011 1:21 pm

That's a concern, sounds like a thread issue, low experience tech or apprentice has fitted them.

Let's see what they say, workshop issue for sure.

sven '2' · Post by **sven '2'** » Fri Feb 11, 2011 2:19 pm

Same motor, same problem in my Foz.

+1 for an appy cross threading the plug

Being an alloy head, you might be able to get the plug to bite back into the thread, but this must only be considered a temporary repair. Mine lasted about 200km before it was spat out again, completely stripped.

Two solutions

1. Helicoil

2. Pull the head off - 2nd hand head or +/- (1) above

I went with a Hellicoil with the head insitu - it is a bastard to get to, and as such, the good people at Rising Sun did the work for me.

Start with (1), but go back to Subaru to sort who is going to do - it is an art using these things, and mobile guys that do it all day, day in, day out are pretty good.

Goodluck

sven '2' · Post by **sven '2'** » Fri Feb 11, 2011 2:24 pm

Just saw you are in SA

For an A1 mobile, J W Lawarence in town have being this sort work 30 years - if Subaru stuff you around too much

Gremlins · Post by **Gremlins** » Fri Feb 11, 2011 6:39 pm

Thanks for the info sven 2, very interesting to see you had the exact same issue. I've used J W Lawrence before a couple of times and the results have always been excellent. Was wondering about the helicoil option with the head in situ - looked like it would be difficult and I had my doubts if it would be feasible.

I had a call not long ago and was advised the car was ready to be picked up - the explanation was the lead was faulty and not locking on the plug properly and we've replaced the lead and it's all good to go. I wasn't happy with that because there is no way I can see how that lead can reverse itself up hill and out of that hole. As far as I can see that lead should just sit there even if it's not clipped to anything and it wasn't just moving up a bit it was all the way out until it hit the battery which stopped it. Anyway, they are now arranging an independent company like J W Lawrence (can't remember the name though) who is going to meet with me at the workshop to examine the thread. Will be interesting to see how this goes.

Jeff · Post by **Jeff** » Fri Feb 11, 2011 7:25 pm

I have seen this a couple of times and each time it has been fixed by just replacing the plug. They have a washer on them that if faulty can allow compression past.

Post by **Alex** » Mon Feb 14, 2011 10:12 am

i had a lead pop off once on my ej22 l-series. The lead was faulty and the pins needed to be bent back in to click onto the top of the plug