Swapstar Posted May 11, 2011 Share Posted May 11, 2011 My 05 LGT started this eratic behavior a couple of weeks ago and I have been trying to troubleshoot it but i'm running out of ideas. i wanted to get some input here before i throw up the white flag and send it to the mechanic. so here is what happens. Car starts up fine, drive around fine even pulls pretty strong after it warms up a little bit. the trouble comes when the car is running hot and i open the throttle up. the car will skip and then start to sputter and loose power. it will then proceed to die out and upon trying to start it back up again, it seems like it struggles to even hold idle and will even backfire. i'm trying to brainstorms ideas as to what is wrong and have narrowed it down to something electrical. my reasoning for electrical fault is that if it were mechanical, the problem would be evident upon initial cold start up. I had the idea that it could be the AVCS solenoids (OCV's) getting stuck or maybe the cam sprocket is getting stuck causing the overlap into the exhaust valve opening and having all the unburned air fuel pass through and get ignited as it hits the hot exhaust manifold. Just wondering if anyone has ever experienced anything like this or have any ideas as to what is causing this to happen. Thanks. Link to comment Share on other sites More sharing options...
Swapstar Posted May 11, 2011 Author Share Posted May 11, 2011 bump no one has had anything similar happen before? Link to comment Share on other sites More sharing options...
Max Capacity Posted May 12, 2011 Share Posted May 12, 2011 Sorry I can't be much help. Funny I didn't notice this thread yesterday. I sometimes wonder if for some reason not all the threads appear all the time. I'm sure one the the guy's who are really knowledgable will pick up on this thread soon. My first guess would be the intake o-rings. But it's fine on cold start up. I doubt it's anything to do with mechanical, I'm thinking electrical or oil pressure system related, such as a sticky valve in the AVCS or something like that. If no one else chimes in, may be flush the oil system with a can of Gunk motor flush. 305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD). CHECK your oil, these cars use it. Engine Build - Click Here Link to comment Share on other sites More sharing options...
Swapstar Posted May 12, 2011 Author Share Posted May 12, 2011 Thanks for your input. I was thinking flushing my engine with the motor flush to be my next move. That and start randomly swapping out sensors and coil packs with my other working 05 LGT. It did throw misfire codes on all four cylinders once but it's not consistent enough to make anything out of it. The only thing consistent is that it'll just loose power and die once if I get on the throttle after it's reached normal running temps. Link to comment Share on other sites More sharing options...
Swapstar Posted May 14, 2011 Author Share Posted May 14, 2011 i drove around today and was running fine. I unplugged the maf to eliminate that as a possibility of something that need to be replaced. but the same problem arose. i uploaded a video on flickr to see if anyone who saw it would be able to see anything i'm missing. [ame=http://www.flickr.com/photos/13021102@N00/5719540283/in/photostream]MOV03450 | Flickr - Photo Sharing!@@AMEPARAM@@http://farm4.static.flickr.com/3635/5719540283_7239648631_m.jpg@@AMEPARAM@@5719540283@@AMEPARAM@@7239648631[/ame] still haven't gotten around to the engine flush. I've also had the idea that it could be the water temp sensor throwing a bad reading when the car is running hot. another idea would be the crank angle sensor also. Link to comment Share on other sites More sharing options...
mwiener2 Posted May 14, 2011 Share Posted May 14, 2011 dead fuel pump.... maybe engine flush won't do squat for you My Mods List (Updated 8/22/17) 2005 Outback FMT Running on Electrons Link to comment Share on other sites More sharing options...
Swapstar Posted July 29, 2011 Author Share Posted July 29, 2011 reviving this thread for anyone that runs into the same problem again in the future. the problem turned out to be the crank angle sensor. this was figured out after swapping plugs, coil packs, fuel pump, map, and cleaning the maf. the crank angle sensor took 5 min to replace. man...i'm kicking myself for not exploring the simple solution first. on the brighter side, i'm getting pretty good at swapping spark plugs and coil packs. thanks for everyone's input on this one, I appreciated it. Link to comment Share on other sites More sharing options...
frank_ster Posted July 29, 2011 Share Posted July 29, 2011 humm .. crank sensor by the way the tach is jumping around faster than the engine can actually change speed. pull the crank sensor ( under altenator ) and see if its covered in debris or metal .. new one is abouut 40$ from autozone Now that's thinking out of the boxer! fyi all 05 + legacy's have built in code reader Link to comment Share on other sites More sharing options...
AWDaholic Posted July 29, 2011 Share Posted July 29, 2011 Old mechanic's axiom: replace teh cheapest part, FIRST! Work your way up the money-tree, from there. Link to comment Share on other sites More sharing options...
Swapstar Posted July 30, 2011 Author Share Posted July 30, 2011 AWDaholic: lesson learned indeed. frank_ster: I pulled it and there was no vision sign that the sensor was bad. I had spare one from another engine that was known to run perfect and once i put it in all the problems went away. that's how i knew it was a bad crank angle sensor. I saw one online somewhere for 15 bucks but that was the price before shipping. Link to comment Share on other sites More sharing options...
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