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Discussion Starter #1
So as the title states I have a 99 Legacy Outback 2.5 that has recently developed a no spark issue. Thus far I have cleaned the IAC (I had read a clogged IAC can cause the ECM to kill spark) replaced CPS, and removed timing cover to verify the car didn't jump time. This was a rather sudden develpment, drove the car to work no issues, went out after 8 hours to go home the cranked the car over, which it did with no issues but she wouldn't fire. I have ohmed out the coil it checks out just fine and I am getting 12.26v to the center pin on the plug coming into the coil. Now I threw a test light on the center pin (#2) of the plug and cranked the engine, and expected to see the light pulse as the engine cranked over however the light remained constant. My assumption was the ignition control module would be killing the 12v to the coil to fire it so either I am wrong here OR the ICM is dead not sure which and that is why I am here. The only code I currently have is a P0420. Also a side not after pulling the timing cover, and the coil, then installing the coil the car fired right up, three times in a row and ran perfectly. Came back an hour later and back to the no spark situation. Anybody have any thoughts on this? Any test procedure on the ICM? I'd rather not drop $150 on a part that may or may not be bad.
 

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Your car has a separate igniter that triggers the coil. I believe it's mounted on the firewall. There have been cases of the igniter failing -- not too common, but possible.

The 12 V on the center (of the three) pins at the coil connector is a good start. However that's the 12 V supply to the coil, so it shouldn't change noticeably (when tested with a light) when the ignition is working.

The other two pins of the connector go to the igniter.

There's also the possibility that a bad connection or bad ground is a factor in light of the engine working three times after some components were removed and re-installed.
 

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coils and igniters can fail, any part can, but they don't fail often. so if you cannot test and find the bad part, i suggest installing a used coil and igniter.

and i agree with OM, if it fired after the re-install of the coil you are in the right neighborhood.
 

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Discussion Starter #6
How did you confirm no spark vs no fuel pressure?
I pulled the plug wires off the coil, made contact with a screw driver held the screwdriver about 1/8" - 1/4" from the intake (Which I verified was in fact grounded with my DVOM) cranked the engine and no spark. I am getting fuel I can smell it.
 

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Can you access the other two (outer) pins on the three pin connector at the coil with your digital Voltmeter? If so, then there should be 12 V at each when the key is at on but the engine isn't turning, and then pulsing voltage at each when the engine is being cranked. If there's no 12 V, then the coil could be defective. If there's 12 V, but no pulsing, then the igniter isn't signalling the coil. Next step (probably the easiest) is to pop in a replacement igniter -- they don't fail often, and really aren't a "wear" item, so, as was suggested, a used one can be tried.

Alternatively, if you can access the igniter connector, one of the harness pins connects to ground, two go to the coil connector, and two go to the ECM. The latter two should also show some pulsing when the engine is being cranked, although I'm not sure of the Voltage levels involved.

It's not likely the ECM is faulty (but not impossible).
 

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I pulled the plug wires off the coil, made contact with a screw driver held the screwdriver about 1/8" - 1/4" from the intake (Which I verified was in fact grounded with my DVOM) cranked the engine and no spark. I am getting fuel I can smell it.
For others reading this I just want to make a safety point:

Do not hold the screw driver when doing this test. The thousands of volts running through the wires can kill.

Very serious!
 

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Discussion Starter #9
For others reading this I just want to make a safety point:

Do not hold the screw driver when doing this test. The thousands of volts running through the wires can kill.

Very serious!
While it is high voltage it is very low amperage, I have been nailed by Chevy HEI systems on a few occasions while it is not fun unless you are elderly, and or have a health condition of some sort I highly highly doubt death is likely. Now having said that holding the metal part of the screwdriver is probably not a good idea unless you want to feel several thousand volts surging through you :)
 
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