WoodsWagon Posted February 22, 2009 Share Posted February 22, 2009 1997 outback 2.5l, automatic Spark on the rear half of the coil pack, none on the front. Plugged in spare coil pack, same thing, spare ingitor, same thing. Won't start, but will cough and backfire. the front coil will generate one spark when you first crank it, and one when you stop, but won't fire properly like the rear coil is. OBD2 data list says the pcm thinks the motor is turning 25 rpm when its stopped and when its cranking. Doesn't change. Front o2 is listed at 0.35v, even with the sensor unplugged. rear 02 is at 1.25v. cam and crank sensors both seem to be ok, so does the timing belt and the pullys all line up. the manifold ground and the starter ground seem to be ok. I'm thinking the pcm may be done. Any thoughts? Quote Link to comment Share on other sites More sharing options...
davebugs Posted February 22, 2009 Share Posted February 22, 2009 Never had that one. Infact if the cam/crank semsors were bad I wouldn't expect any spark and you've already swapped the coil pack. Unless a plug wire or plug is really bad? I'm parting a 97 Legacy now. Never needed to swap an ECU. Tell me where it is and give me something for me labor/shipping/packaging and I'll send it to you. I know it worked. It's from a 2.2 car that had tranny issues. I've done a decent amount of 2.2's inplace of 2.5's so I think it would work. Dave Quote Link to comment Share on other sites More sharing options...
Cougar Posted February 22, 2009 Share Posted February 22, 2009 The ignition problem may be due to a bad ECU but there are other things that could cause the trouble. Did you check the voltage to the bad coil and compare it to the good one? There may be a wiring problem to the non working section. Another thing that can happen is a reluctor lobe on the crank sprocket can break off and then the ignition signal is changed. You may be able to check for a problem with the ECU outputs to the coils by checking the the resistances of the working section and comparing them to the non working section. Compare the resistances of each lead to ground and across the outputs. There may be a wiring problem to the O2 sensors also. Quote Link to comment Share on other sites More sharing options...
davebugs Posted February 22, 2009 Share Posted February 22, 2009 Would an O2 sensor problem really cause no spark? I would have NEVER checked that. Quote Link to comment Share on other sites More sharing options...
Cougar Posted February 22, 2009 Share Posted February 22, 2009 Sorry, I didn't mean to imply that the O2 sensors were causing a starting problem, just that there may be a wiring problem causing the trouble with them. Quote Link to comment Share on other sites More sharing options...
abog Posted February 22, 2009 Share Posted February 22, 2009 If i remember correctly, the readings that you are getting for 02 are baseline or fail safe readings. Quote Link to comment Share on other sites More sharing options...
nipper Posted February 22, 2009 Share Posted February 22, 2009 Oddly my haynes book says you have an ignitor. I was under the impression that the ignitors went away. Since you have power to the coils (one set works) we can rule that out, as they have a common hot lead. Then from the coils it goes to the ignitor (red/grn and blue). The ignitor is Yel/violet and Yellow/blue then it goes to the ECU. Ignitor is by the dog-bone motor mount. nipper Quote Link to comment Share on other sites More sharing options...
porcupine73 Posted March 5, 2009 Share Posted March 5, 2009 I recall seeing something about some grounds that could back out at the ECU connector or loosen up or something causing this sort of issue. I think it had to do with F27. Quote Link to comment Share on other sites More sharing options...
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