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Subaru 2.0 Twin Turbo Legacy 2.0 1998 Import - Misfire after plug change - Fixed #

Posted by Charlie Hirst on June 7, 2011, 9:37 pm

Year of Manufacture *: 1998
Engine Size and Code *: 2.0
( Optional ) Scanner Used: launch diagun

I've replaced the spark plugs with the correct ones supplied via the local subaru dealer and now it misses/pops every 30 seconds/minute.I also changed the air,oil filter and oil. No fault codes came up on my launch diagun but the o2 sensor voltage readings were all over the place.It was fine before it came in.
Any ideas?

Re: Subaru 2.0 twin turbo legacy import (B4 or 5)

Posted by Pete Mutlow <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=UKAT1569' width='330' height='300' border=0 style='border:none;'> on June 7, 2011, 10:40 pm, in reply to "Subaru 2.0 twin turbo legacy import (B4 or 5)"
Peter Mutlow

Hi Charlie,

If this was my problem, the first thing I would do is put the original plugs back in and see what happens and then chase it from there. It may save a lot of diagnostic work unless of course you have already tried that.

Regards

Pete M

Re: Subaru 2.0 twin turbo legacy import (B4 or 5)

Posted by Dave Harney <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=UKAT2603' width='330' height='300' border=0 style='border:none;'> on June 8, 2011, 7:28 am, in reply to "Re: Subaru 2.0 twin turbo legacy import (B4 or 5)"

Hi Charlie,
Have you got the plug leads/coil packs on correctly !!

Regards
Dave

You can trim a sheeps wool many times, but you can only fleece it once !

Re: Subaru 2.0 twin turbo legacy import (B4 or 5)

Posted by Charlie Hirst <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=ukat3269' width='330' height='300' border=0 style='border:none;'> on June 9, 2011, 3:26 pm, in reply to "Re: Subaru 2.0 twin turbo legacy import (B4 or 5)"
Charlie Hirst

I did change back to the original plugs which made no difference. I swapped around the coils which didn't change anything. As I struggled to fit them in through the tight gap I was wondering if the coil boots might have cracked. I'm in process of obtaining a new coil to swap/pinpoint fault. But if a coil was shorting to the engine block, can I identify that with a multimeter or otherwise? I couldn't see any sparking/arcing.

Re: Subaru 2.0 twin turbo legacy import (B4 or 5)

Posted by Pete Mutlow <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=UKAT1569' width='330' height='300' border=0 style='border:none;'> on June 9, 2011, 9:21 pm, in reply to "Re: Subaru 2.0 twin turbo legacy import (B4 or 5)"
Peter Mutlow

Hi Charlie,

I don't have a COP tester to test the coils but I visually inspect the boots and if there is any arcing it can be seen by a small burn mark. Failing that, I attach a plug lead between coil and plug and then a timing gun to that. Start engine and watch for intermittent flashes from the timing gun. Simples!

Regards

Pete M

PS. Hope no debris has dropped down the plug hole

Re: Subaru 2.0 twin turbo legacy import (B4 or 5)

Posted by Charlie Hirst <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=ukat3269' width='330' height='300' border=0 style='border:none;'> on June 10, 2011, 11:08 am, in reply to "Re: Subaru 2.0 twin turbo legacy import (B4 or 5)"
Charlie Hirst

FIXED! The owner had been looking on Scooby forums & mentioned swapping around coil leads. I did that & hey presto. All working fine. I was adamant it couldn't have been a scoolboy error.

So for future reference, to all out there; there is 2 white coil leads which attach to the 2 front coils & 2 black leads to the rear coils.

Many thanks to Pete & Dave for your valuable advice.
Charlie Hirst

Re: Subaru 2.0 twin turbo legacy import (B4 or 5)

Posted by Pete Mutlow <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=UKAT1569' width='330' height='300' border=0 style='border:none;'> on June 10, 2011, 6:24 pm, in reply to "Re: Subaru 2.0 twin turbo legacy import (B4 or 5)"
Peter Mutlow

Interesting. I assume you are talking about the LT leads. Would have thought if they were the wrong way round then the cylinders would fire in the wrong order. Unless I am missing something

Regards

Pete M

Fixed #

Posted by Charlie Hurst on June 10, 2011, 7:16 pm, in reply to "Re: Subaru 2.0 twin turbo legacy import (B4 or 5)"
Message modified by board administrator June 16, 2011, 5:25 pm

Yes it was the HT leads that got mixed up when removing coils to gain plug access. Very tight space around battery. Washer bottle was removed. It would start & run rough on tickover & acceleration.

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