A problem has developed with our 1996 Legacy Outback, and I'm hoping you
folks can help me narrow down the problem before I take it in for
service again. The symptoms are that in the morning, when the car is
still relatively cold, it will lose power during acceleration (like when
getting on the freeway). Sometimes it will be so bad as to stall out,
and I'll need to pull over and wait for a couple minutes before starting
the engine again. After that, it seems to be ok. Oftentimes, the
"check engine" light will come on for a few minutes or hours, then go
off again.

This problem started last fall. It happened a few times before the
check engine light came on. The first time that happened, I took it to
a local repair shop. They put it on the computer and read the code --
misfire on #3 and 4 cylinders. The mechanic did a maintenance tune-up
(which included replacing the plug wire set, plugs, fuel filter, oil and
filter, fluids, top radiator hose, antifreeze, carb cleaner).

The problem might have gone away for a couple weeks, but it came back.
It was time for the 90K mile service anyway, so I took it back to the
mechanic a few months later. He read the codes from the check engine
light again, and found the same thing -- misfire on #3 and 4 cylinders.
He did the 90K servicing, but didn't find anything new about the
problem.

The problem continued for awhile, then went away for a couple months.
It's been a bit warmer lately, so that may have had something to do with
it. This week was a little colder and rainy, and the problem hit again
yesterday. It lost power and stalled out, but this time it was while I
was decelerating, coming up to a stop light. Otherwise the same
symptoms, and the check engine light is on again.

I need to get this fixed! I don't know much about car engines, but I've
got the Chilton's manual and I'm fairly handy. I'm hoping someone can
either suggest some things I can try on my own to isolate or repair the
problem, or else give me some ideas to bring to the repair shop so that
I'm not hit with a high troubleshooting bill. Any help is appreciated.
Thanks!

I found an old message
(http://groups-
beta.google.com/group/alt.autos.subaru/browse_thread/threa
d/88998ae44c320fb6/4172b9107100e7a9?q=%22check+engine%22+304+group:
*subar
u*&rnum=3&hl=en#4172b9107100e7a9) that indicates it might be the
alternator going bad. Does that make sense? Is there a way to test the
alternator?

Dave N <daven (AT) mailinator (DOT) com> wrote in
news:Xns967E6B08CAC8Adavenmailinatorcom (AT) 216 (DOT) 196.97.142:

Dave N wrote:

The only thing I can suggest is looking under
the hood at night in the dark while the engine
is running. Look for arcing around the coil
pack. The car should also be cold when you do
this.

I'm guessing that cold and condensation is causing
the coil pack to short out until it gets warm.

Just a guess though...

Thanks, Jim. I'm thinking it's a good guess. I've done a bunch of
Google searches in the last couple hours, and apparently this is a
common problem. It's always tripping the misfire codes for both #3 and
4 cylinders, and one of the things they have in common is the coil pack
(according to a few posts I've found).

So I'd like to try your suggestions. Erm... what is the coil pack, and
how can I find it?

Jim Stewart <jstewart (AT) jkmicro (DOT) com> wrote in
news:vOidnfdChvgqYyffRVn-pw (AT) omsoft (DOT) com:

Hold on, is the coil pack the same thing as the ignition coil? I found
that in my manual. Looks like I need to check primary and secondary
resistance, and maybe replace it. This could be a cheap and easy fix!
Let me know if I'm on the wrong track...

Dave N <daven (AT) mailinator (DOT) com> wrote in
news:Xns967E7A3CCFEDBdavenmailinatorcom (AT) 216 (DOT) 196.97.142:

Coil pack idea and the dark test for ignition shorting sounds good to
me. In addition since it does it during damp/rainy conditions I would
remove and clean the battery terminals AND ground connections as a
oxidation film may have built up and absorb moisture.
"Dave N" <daven (AT) mailinator (DOT) com> wrote

Dave N wrote:
Here's a picture of my car. The coil
pack has the 4 red wires coming out of
it. It's called a coil pack because
there are 2 coils and each coil is double-
ended, with each end going to a plug.

http://www.jkmicro.com/jim/coilpack.jpg

As the the resistance check, you can do
it, but it may test good and still be
bad. Given that your problem goes away
when the car is warm, I suspect that it
only fails when it is cold and under
load.

Still just all speculation, but that's
about all you can do at this point.

Thanks, Jim, I really appreciate your help. Both of these trips to the
repair shop cost me $400, and it looks like the coil pack is about $85.
That seems like a good suspect, so I'll check and probably replace it.
If it might save me the cost of another repair shop bill, it's worth a
try. (Of course, now that summer's here, I may not know if that fixed
the problem until fall.)

Jim Stewart <jstewart (AT) jkmicro (DOT) com> wrote in
news:eJGdnVvHB_4SiibfRVn-ow (AT) omsoft (DOT) com:

Thanks, Edward. I'll follow your suggestions in addition to the coil pack
test.

"Edward Hayes" <erhayes (AT) worldnet (DOT) att.net> wrote in news:CCEue.1013374
$w62.435134 (AT) bgtnsc05-news (DOT) ops.worldnet.att.net:

Interesting stuff on the coil pack resistance. Why not cool down the
coil pack with ice bags for an hour or so and test with ohm meter to
see if things change vs. warm and or drive when you cool down the coil
pack. This way you could isolate the failure mode and part. Ed
"Dave N" <daven (AT) mailinator (DOT) com> wrote