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I've had a solid CEL on occasion recently, and it seems to be associated with the AC. Yours is flashing, and like the manual said, it might be a misfire. You will not get a CEL for a headgasket, as it's an entirely mechanical issue with no ECU oversight. Overheating is the first sign, so if you're not seeing that, don't worry.

I'd recommend resetting the ECU first, driving it for a tank, and noting the return and pattern of CELs, if any. If they disappear, keep driving. If they return, find a local place that can read the code for you for little or no charge, after checking to see if your local dealer will check this for you as a courtesy.

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I've been a Legacy owner and an online presence since 99, so it's mostly by osmosis :)

The best way to drain the battery, in my opinion, is to disconnect the negative terminal and then step on the brake pedal for 2-3 minutes to discharge any capacitors in the electrical system and ECU. Leave it for another 25 minutes and reconnect.

Driving afterwards supposedly does affect how it learns. When I've done it, I just drive like I normally do: sane. Over time, the ECU will learn and optimize, and hopefully forget all of the error codes.

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An interesting problem for sure. It could be a clogged fuel injector or perhaps a low fuel pressure caused by a clogged fuel filter. Also make sure your air filter is good, just in case. A misfire is usually caused by insufficient spark, too little or too much fuel.

I'm having the same problem with mine. When I start her up she runs for a few seconds until the idle drops down and then it stalls. I changed the plugs and wires and the problem still exists. My quesiton is, could it be the coilpack and if so how can I check it to see if it is bad?? Also, if I play with the gas pedal I can keep it running but only above 1500 rpm and it sounds like it is missing a cylinder. Which leads me to believe its the coilpack. Please help!!

GTOWNR

I took it to autozone and they were able to check it. The primary side was out of spec.

GTOWNR

Just thought I'd let you know it turned out to be the injectors, 1 and 3. Runs good now!!