Just heard about this recently, and from the amount of misfire problems I'm seeing here, want to pass it on.

 

Seems there is a "phantom" problem with the later model EJ25 ECUs. Most consistent symptom is an engine which runs perfectly, but will throw a cylinder 3 or 4 misfire code every couple of weeks, usually right after doing 65-70mph and letting off gas. Disconnect battery, reset ECU, runs fine for couple of weeks and poof! suddenly you have a misfire code and a flashing CEL.

 

Here's what I've been told by one of the best diagnostic/electronic guys in the business, Greg at Strictly Automotive in Denver, CO.

 

Nobody, especially Subaru, knows why this is happening. The only permanent cure he knows of is to have the ECU reprogrammed. I understand that there is a company or 2 in California that do this, but I have no idea who they are.

The other possibly less expensive and maybe easier cure would be to find a used ECU with the same part number. The only problem is: how do you know that the "new" doesn't have the same "phantom"?

 

You can throw money at it, try to diagnose it, but if you've addressed the obvious problems and it's still happening, then you have the "phantom gremlin" in your ECU.

 

Not sure if this is a help or another monkey wrench to throw into you guys who are having this problem. :-\

 

Emily

http://www.ccrengines.com

Well this is very interesting...I just posted a problem with cyl 4 misfire yesterday...(see post: here).

 

So is Subaru acknowledging a problem or is this just a theory?

 

Thanks for posting this...at least if I never find a problem I can fall back on the phantom ECU menace.

Thanks for the links.I think we have another case of the phaNTOM Menace. Polack

 

 

 

 

 

 

 

 

 

 

 

 

Well this is very interesting...I just posted a problem with cyl 4 misfire yesterday...(see post: here).

 

So is Subaru acknowledging a problem or is this just a theory?

 

Thanks for posting this...at least if I never find a problem I can fall back on the phantom ECU menace.

Thanks for the info on Misfires. Is this related to the 'hesitation' issue ?. I have a 01 outback wagon, and have had the recurring problem of hesitation for some time. This thing is on its 3rd transmission, and probably heading for a 4th if something is not done about this soon. Have replaced o2, throttle pos sensor, filters, etc. and nothing works. Quite frustrating for this car. Don't really know where to turn, as I have also read it is just the car. BAD NEWS. Hope Subaru acknowledges this issue.