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Strange Electrical Gremlin in 2009NA Legacy

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Hey, this is my first time posting on the forum. I've looked through it quite a few times and it seems like there's really a lot of good information on here. I've been having quite a bit of trouble with my Legacy that I bought a few months ago and I was looking for some insight as to what's going on.


Here is a timeline of the issues I've had. The short timeframe and seemingly random events make me suspicious of an electrical issue but I'm not sure.


July 5- car is bought, good shape minor surface rust on underside. 79000 miles.


July 9- Airbag light comes on and stays on for the duration of a 4hr drive roundtrip. There is heavy rain that day.


August 12- My cousin drives the car from Minnesota to NM for me. He has no issues.


August 18-Driving across Kansas to get to school in Iowa, car begins to die with clutch pressed in at highway speeds. The car continues to idle poorly with clutch pressed in or out of gear for about a month.


September 15- Airbag light comes back on for about 15minutes. Idle seems better.


October 8- Acceleration felt rough at low revs a few days before. On the way back from a very short drive, The CEL and traction lights come on accompanied by. flashing cruise control light. The codes were for a misfire in cylinders 1&2. Strange whining noise coming from around the throttle valve actuator with keys in ignition but engine off.



Any input would be appreciated, thanks!

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The air bag light could be a problem with the air bag indicator by the front map lights. Easy test would be turn the key on and look up and 4 lights should light up and go off after about 10 secs. If one fails to light or it looks dim thats most likely your problem. You can solder the resistors on the led board. But it's always best to pull the codes out of the computer to see what is wrong.

As far as the misfire it can be a cracked spark plug or a faulty wire even a bad ignition coil pack.The whining noise could be a dirty throttle body I had that happen on mine once.

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The passenger air bag light isn't the problem. That preforms normally every time I turn the car on. For the misfire I don't think its a plug or a wire because it was driving okay before suddenly throwing codes for two different cylinders. It seems to me like maybe there's a bad ground somewhere. But if that's the case, I don't understand why it would be causing issues with both the engine and the airbag system. I thought that the ECU and SRS systems were independet?
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airbag light is a common issue, one of the solder joints probably just needs to be touched up due to cracking




throttle body noise is normal


car wanting to die with clutch pedal pressed in is abnormal, unless the battery was disconnected recently, our cars act funny for a few days after the battery has been disconnected.



Not sure what to say about the misfire, I kind of wonder about the condition of your spark plugs and wires. If the spark plug wires are oem Subaru, I can tell you the resistance they're supposed to have. the oem wires I've used have said something like "Packard r15 aips" on them.



I'd try cleaning the maf sensor, it's near the engine air filter. In the second picture, I think that's the air temperature sensor. In the last picture with the two resistors, I think that's what meters the air coming through the intake, but I'm not sure about that. Either way, I'd just spray down everything with something like crc maf sensor cleaner.



some people say you can use brake cleaner, but I don't know, msrp on the maf sensor is around $180, so I'd hate to see you damage it. Though, you can get a new sensor from various dealerships online for around $120-$130, or an aftermarket Delphi for around $90 on rockauto. Denso doesn't appear to sell one for our cars in the aftermarket.




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I hate to reply again, but I'll throw this out there too.. Unless they've been replaced before, chances are your spark plug tube seals are leaking. I wonder if oil is going down toward the spark plugs, and maybe causing them to foul



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Thanks for all the advise! I looked at the wires, they are the OEM Packard's. I pulled the cyl 2 boot out and there was some oil near the top but by the plug seemed dry. The grounds looked okay. They're pretty green but they feel solid. It seems like the spark plus wires and the grounds might be a good place to start.


I'll get some MAF cleaner next week.

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I'd probably go with OEM wires in your shoes, on ebay dealerships sell them for around $45-50. I've heard some aftermarket wires don't give that satisfying click when you plug them into the coil, and I worry they could come loose if they don't click.


If you want to check the resistance of your wires, here's what Subaru says..

wire 1 - 7.1 - 12.1 kohms

wire 2 - 12.1 - 19.9 kohms

wire 3 - 7.7 - 13.0 kohms

wire 4 - 12.3 - 20.2 kohms

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