steamin53 Posted August 28, 2008 Share Posted August 28, 2008 1996 Legacy Outback Auto Trans 2.5 engine. The ECM tests as bad in the fault isolation procedures for code P0505 High Idle. The IAC is clean and functions; it's the computer no doubt. My question is in regard to a statement I read from a used parts dealer that the computer will have to be recalibrated by the dealer after replacement. Is recalibration required, and if so, can only Subaru do it? I need a definitive answer from someone here who knows for sure. Steve Quote Link to comment Share on other sites More sharing options...
sea#3 Posted August 28, 2008 Share Posted August 28, 2008 It should be plug and play , just check the part # on the ECM 's to make sure they are the same . Other than doing and idle learn , which is warm car up to operating temp , turn A/C on for 2 minutes on high then turn off . There should be no worries SEA#3 Quote Link to comment Share on other sites More sharing options...
porcupine73 Posted August 31, 2008 Share Posted August 31, 2008 Never heard of any 'recalibrate' for a soob ECU. Maybe the newest model vehicles would need something like that. Could be some other makes that do require it so the seller makes that generic statement to cover themselves. Also saw this note, it says for '95s but heck it could be worth a shot: http://endwrench.com/images/pdfs/1995SubaruInfo.pdf 1995 Subaru Legacy - DTC P0505 - Idle Control System Malfunction If you encounter a 1995 Subaru Legacy with a DTC P0505 (Idle Control System Malfunction), check to see that the wire pins in connector B22 are securely fastened in the connector. If pin 13 (BY) has backed out of the connector, you will lose two grounds at the ECU. Actually I think I remember some time back someone having this issue on a '96 and we looked up some diagrams and stuff.... here's what I have Quote Link to comment Share on other sites More sharing options...
idosubaru Posted August 31, 2008 Share Posted August 31, 2008 recalibrate a 96 ECU - definitely not. just ignore whoever said that, just regurgitating or CYA in effect. first of all i know...second of all i've even done it on a 96 even. Quote Link to comment Share on other sites More sharing options...
steamin53 Posted August 31, 2008 Author Share Posted August 31, 2008 Thanks guys, I appreciate your help. Connector B-22 looks like it will be a real joy to get to . I can't imagine a pin backing out of the connector unless work was done and it was disconnected or something. We have changed the engine (multiple times ) but it's been working fine for 6 months or so. I'll save that "fun" for the last test as I have an ecu on the way now. The voltage tests of the cricuits from the ecu to the IAC that indicate the ecu at fault so I doubt it's the connector. One never can tell though. Thanks again. Steve Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted August 31, 2008 Share Posted August 31, 2008 Subaru ECU's are rarely at fault for anything. They are die-hard components and although I have owned several dozen Subaru's, and I have a pile of ECU's in the garage I have NEVER seen one fail. It's always something else. Apparently you can kill some of the older one's if you connect the battery backwards for more than 30 seconds or so. I've never met an idiot who tried it though. GD Quote Link to comment Share on other sites More sharing options...
steamin53 Posted September 18, 2008 Author Share Posted September 18, 2008 Well boys this thing is kicking my tail. I changed the ECM and cured the high idle condition. On cold start it idles at about 1500 till it begins to warm then slowly drops to 750 to 1000. Holds smooth idle at about 750 in gear and adjusts for load with AC, headlights, etc. BUT, it still occasionally throws a CEL code. Sometimes Vehicle Speed Sensor P0500 other times Idle Speed Control P0505. This underway at highway speed and without any apparent deviation in the idle speed system. The engine is running better than ever. The speedometer works fine. Of course I clear(ed) the codes with my OBDII scan device. Any ideas? Steve Quote Link to comment Share on other sites More sharing options...
porcupine73 Posted September 18, 2008 Share Posted September 18, 2008 Any ideas? Did you have a chance to check that B22 connector? Quote Link to comment Share on other sites More sharing options...
steamin53 Posted September 18, 2008 Author Share Posted September 18, 2008 Porcupine I must admit I haven't checked it yet. Help me with the geography if you can. The illustration shown in the thread "appears" to place it forward in the engine compartment. I can only conclude that would be under the intake, but I don't recall any connectors of that type when I had it off for the engine swap. Is is possibly one of the set of 2 or 3 mounted on the aft passenger side of the engine? Steve Quote Link to comment Share on other sites More sharing options...
steamin53 Posted September 23, 2008 Author Share Posted September 23, 2008 I found the connector and checked and cleaned all contacts. Unfortunately no change. I believe the problem is that once the engine has warmed it may be idling just a little slow. Sometimes it drops to 500 rpm on the tach. As I have changed the Idle Air Control Valve I wonder if the duty cycle is set right, and if not, if that's causing the fault. I don't know how to set this but I'm wondering if I set it just as the OEM one was set by loosening the screws on the top and moving the plate to match the position of the original if it will make a difference. Any ideas?? Steve Quote Link to comment Share on other sites More sharing options...
steamin53 Posted September 23, 2008 Author Share Posted September 23, 2008 I believe I'll start a new thread for this idle air control valve duty cycle adjustment question. Steve Quote Link to comment Share on other sites More sharing options...
torxxx Posted September 23, 2008 Share Posted September 23, 2008 technically by ASE standards, any ecu thats replaced needs to be flashed. I dont care if its a subaru with the exact same serial number. its just like a computer, you dont upgrade your processor without a fresh windows install. flash can be easily done with a laptop and a serial cable with the software thats offered through the board. Ford, Chevy and dodge all require the ECU to be flashed, I dont see how subaru, mazda, mitsu, nissan etc are exempt from this. All computers hold memory from the previous installation Quote Link to comment Share on other sites More sharing options...
steamin53 Posted September 29, 2008 Author Share Posted September 29, 2008 That's an interesting thought. I did a search on reflash but I'm not finding the info you mentioned. Can you steer me to the discussion? Steve Quote Link to comment Share on other sites More sharing options...
idosubaru Posted September 29, 2008 Share Posted September 29, 2008 technically by ASE standards, any ecu thats replaced needs to be flashed. that's a ridiculously mis-leading comment to include in a thread for someone that needs help here. notice i didn't say it's "not true", it's just misleading and completely irrelevant for these reasons: to the original poster, please completely disregard that comment. it's obvious this comment isn't based on any real world significant ECU work on a Subaru. for those of us that have actually swapped dozens of ECU's, relax and realize it's done all the time without any "reflashing". plug and play is the name of the game. drive to my house and i have a yard full of subaru's and boxes of ECU's...i can swap them all day long and the cars run fine...been there, done that...dozens of times and so have others. IF for some odd reason your ECU did have software problems, the solution is not a reflash but to buy another ECU for $35 and install it. but that's not your issue anyway. Quote Link to comment Share on other sites More sharing options...
tabo Posted July 29, 2009 Share Posted July 29, 2009 technically by ASE standards, any ecu thats replaced needs to be flashed. I dont care if its a subaru with the exact same serial number. its just like a computer, you dont upgrade your processor without a fresh windows install. LoL... and for the record, you can certainly upgrade a processor without reinstalling Windows, in fact you probably don't need to do anything. You can pull the hard drive out of an old machine and put it in a new one without having to reinstall windows, although you will have to upgrade some drivers. But you certainly don't need to reinstall. Of course, everyone tells you to reinstall because it's good to have a clean install, and it's much easier to tell someone to reinstall than to add drivers, but in no way is it necessary. Quote Link to comment Share on other sites More sharing options...
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