"02" outback ECU question?

[schekan]

I need to replace my ECU. Does it matter if it is from a manual or an automatic for this year?   

 

 

 

 

I have a manual trans and bought one from ebay. Same numbers as the one i pulled. I installed it and ran it for about 20 minutes. I shut it down and checked it with my OBD2 reader just to see if it had any lingering codes. All was good and no CEL. The next day i started it and after 5 minutes running it through 2 codes related to the torque converter.

 

 

 

 

 

Any help would be greatly appreciated.

 

 

Thanks....

[johnceggleston]

what were the code numbers.?

 

if the part numbers were the say on both parts, it should be ok.

 

were the codes you got the same ones you had on the old computer?

 

are you sure the old one was the original one?

 

why did you think you needed a new computer?

 

some codes require 2 drive cycles before it will throw a code, i think.

[schekan]

My ecu is the original. I dont remember the code #'s but both were related to the torque converter. It was used from ebay, maybe it was bad. I got my money back.

 

As far as my problem, my original ecu has crazy idle problems. It does not throw any codes. Just crazy idle.

 

I know it is ecu related because i found an outback in a u pull it bone yard. It was an 01, numbers were different but plugs were the same. So for $15 i said what the hell.

 

I plugged it in and the car idles great, runs good as well. Its running a little rich with this ecu and the CEL is on solid. The code is for the "atmospheric preasure sensor" on my ecu the sensor is located on the ECU board. This ECU does not have it, so it throws that code.

 

So in a nutshell i want to put a good ECU in it so it will run normal and no CEL.

 

THANKS for the reply by the way..

[Gloyale]

ECUs fail very rarely.

 

I would get a correct ECU for the car.

 

Then start following the error codes from there.

 

I don't think your ECU is the problem.

 

 

IIRC, 01 is MAF based, 02 is MAP based.  this could be the ECU difference.

 

 

If you are chasing idle issues, start with cleaning the IAC.

[mikaleda]

ECUs fail very rarely.

 

I would get a correct ECU for the car.

 

Then start following the error codes from there.

 

I don't think your ECU is the problem.

 

 

IIRC, 01 is MAF based, 02 is MAP based.  this could be the ECU difference.

 

 

If you are chasing idle issues, start with cleaning the IAC.

If changing the ecu made it idle correctly than the IAC is fine and he is probably right about the ecu being the problem.

[Gloyale]

If changing the ecu made it idle correctly than the IAC is fine and he is probably right about the ecu being the problem.

 

No.  Because he said that ECU had a code lit all the time.  This means that ECU was could be in open loop all the time.  Ignoring alot of other parameters and going on a "default" map.  The default map would hold a steady idle. (or send no IAC signal allowing the IAC to rest, yielding steady idle)

 

whereas, in closed loop, the ECU is monitoring and adjusting all the time.  a bad MAF, or an IAC that tries to respond but won't properly........could cause the idle to surge while the ECU tries to figure it all out.

 

ECU is the absolute LAST thing to suspect, unless there is a problem with the CEL illuminating at KOEO.

[mikaleda]

No.  Because he said that ECU had a code lit all the time.  This means that ECU was could be in open loop all the time.  Ignoring alot of other parameters and going on a "default" map.  The default map would hold a steady idle. (or send no IAC signal allowing the IAC to rest, yielding steady idle)

 

whereas, in closed loop, the ECU is monitoring and adjusting all the time.  a bad MAF, or an IAC that tries to respond but won't properly........could cause the idle to surge while the ECU tries to figure it all out.

 

ECU is the absolute LAST thing to suspect, unless there is a problem with the CEL illuminating at KOEO.

Ahh, my bad I totaly forgot about subarus limp mode feature. You are correct.

[Caboobaroo]

ECUs fail very rarely.

 

I would get a correct ECU for the car.

 

Then start following the error codes from there.

 

I don't think your ECU is the problem.

 

 

IIRC, 01 is MAF based, 02 is MAP based.  this could be the ECU difference.

 

 

If you are chasing idle issues, start with cleaning the IAC.

'01 is MAP based as well. '00 was the first year of the MAP based 2.5 as it started with the SOHC. Now '99 SOHC Foresters were a MAF based ECU.

 

If the ECU came from an auto, it won't work for the manual which is why you're getting transmission torque converter permission codes. ECU is waiting for input from the TCU in regards to torque converter but since it doesn't have either a TCU or a torque converter, thus why the CEL is prompted on.

 

Some codes take two run cycles for them to come back. It doesn't matter if it's a quick startup, shut off and restart or overnight.

[schekan]

OK, first thanks for the feed back.  Let go into this a little more. I have an 02 outback. the original ECU does NOT throw any codes at all. As far as my idle, all components have been swapped and my TPS is brand new. IAC has been replaced 3 times with bone yard picks that looked brand new. (I have several u-pick yards up my way)

 

Nothing could control the idle. When shifting in between gears it would rise at a steady pace to around 4000 rpm and sometimes higher. almost like the cable was stuck also surging.

 

I have read in this forum and others that Subaru's require Re-flashing of the ecu sometimes for idle and other issues. My ECU has the Atmospheric preasure sensor attached to the board itself.. I know this for a fact.

 

So when I pulled the ECU out of the car at the junk yard i plugged it in. Car runs and idles fine for around a year now and 25,000 miles. It does throw the Atmospheric preasure sensor  voltage out off range code.

 

I thought if it's just a bad sensor on my Junkyard doner I will de-solder it from my original and move it over to doner from the "01" Well the "01" does not have this sensor on it. Thus the reason I have a solid CEL for that one code. 

 

As far as components causing my idle issue I think i just disproved that. The original ECU is telling it to idle the way it is. And I would like to get an original so the light will go out. Or take the car to Subaru and have it flashed. My issue with re-flashing it is something cause the ROM to get corrupted, and if i flash it it may only be a temp fix as whatever caused it to go bad the first time will certainly cause it again.

 

So my real question is.

 

Does it matter if the ECU comes from an automatic or standard for an "02" outback?

 

ECU D6M 1T

22611 AG53A

JA18000 D6M

 

This is the tag numbers from the original. When bying from a junk yard or ebay it is listed as just the ecu. Some will go as far as to say it was from an automatic.

Edited March 29, 2013 by schekan

[ivans imports]

I have repaired two 00-02 outback ecus one they pinched the wires in bell on motor swap other the o2 wires melted on exhaust both had bunt traces from the main driver chip to the board i had to use one single strand of wire sodeired axross the burnt trace but was able to do it. Used a big magnafying glass and a shaved down soilder pen was very difacult but doable. Anyway if you have a auto ecu it will be looking for its auto trans controler ecu they share alot of comunacation and one can not work without the other. I ? whearther it was a ecu problem or not have never seen one fail without a reason

[schekan]

I have repaired two 00-02 outback ecus one they pinched the wires in bell on motor swap other the o2 wires melted on exhaust both had bunt traces from the main driver chip to the board i had to use one single strand of wire sodeired axross the burnt trace but was able to do it. Used a big magnafying glass and a shaved down soilder pen was very difacult but doable. Anyway if you have a auto ecu it will be looking for its auto trans controler ecu they share alot of comunacation and one can not work without the other. I ? whearther it was a ecu problem or not have never seen one fail without a reason

So that would explain why the ebay one i bought threw the codes related to an auto trans. As far as these not failing without a reason i could see your point. But why is the car running fine with an ecu from another vehicle although its the incorrect one. but it runs fine (Except for the CEL) if i had a component failing or shorting it would still fail with this ECU.

 

 

 

 I may call Subaru and see how much they want to flash it. And see if that helps. The car is Not drivable with the original ECU. I will find out monday what they want to do it.

 

Thanks for the feedback  

 

 

 

[ivans imports]

Mabee cause the problem is realted to somthing that repalcement ecu did not have eg standard stuff netral position clutch imput cruise ecu airbag ecu idle motor stuff like that thats different between std and auto. I have had cars run better or different with other ecu but could be in default or in limp mode will run good but cant learn or addjust. I whould put in origanal ecu and start diagnosing 1 thing at time. Anuther good way is find exact outback as yours and put your ecu in it and see how it runs do not put there ecu in your car as if there is problem with your car can damage there ecu. I had to do thiss to diagnose the last bad ecu i had and to test it after repair. remember the ecu is very smart and can go around sensers if it dosent see what it wants