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It started with me noticing lousy fuel economy on my last tankful.

Then a few days later I noticed when it was cold/damp it stumbled.

The next day It stumbled again and this time the check engine light came on.

Next day the dealer read the code and reported a misfire on cylinder 2.

 

I was told that the most likely cause was # 2 wire but that it might also be the coil.

 

I had #2 wire replaced and the firmware re-flashed. $150 Canadian

 

I couldn't get any specific info as to what the latest firmware would do but I was told that if there was new firmware it would automatically be installed.

 

So far this is a fix! and the car is running smoother than I can remember.

I feel that everything from the fuel mapping to the shift points has changed.

 

The auto is super smooth, really pretty civilized if you consider it's all wheel drive.

 

I wasn't sure but my wife noticed this improved smoothness, linearity, and throttle control also.

 

If I'm not on cheap drugs this is something I would definitely recommend.

 

David

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After a couple of days I can report more on the new re flash.

Almost perfect even boring smoothness, transmission guessing is way down.

More torque converter fanning so less sluggishness. but it is fanning (500 rpm (guess) or so and then just locking up invisibly. This gives the desired result.

Shift transitions are smoother. I heard when I got the car that the 4eat was good for a conventional automatic. And now I believe it.

It's like the computer now knows that your driving an automatic and will now behave accordingly.

 

 

Engine is dead quiet even when started at - 10C

Edited by subaruplatt
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[...] Can somebody explain the difference between a re-flash and the normal resetting of error codes?

I can't offer much useful on your other questions, but perhaps I can provide some insight into the usage of flash memory in your car. You may already know some of this...

 

Computer memory is of two basic types -- volatile (data is lost when the power is removed) and non-volatile (retains data even when not powered). "Flash" memory is of the non-volatile type, and it's where the firmware (operating instructions) for the ECU (computer) is stored. Volatile memory is where error conditions and data for adaptive strategy (fuel trim, for example) is kept.

 

Re-flashing wipes the ECU's non-volatile memory clean of the previous programming, and re-installs it. It could be the same program, but more typically it's an update based on improvements determined over time.

 

When the ECU is just "reset", that's when the error data and adaptive info is erased from the volatile memory and the ECU defaults to certain basic settings. It can be done via a data link (OBD-II port, for example), or just by disconnecting the car's battery for a sufficient length of time.

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Thanks for the info! In my quest to gain understanding I have stumbled upon and open source ECU Flashing software for Subaru s that also works with Macs! Does life get any better?

http://www.openecu.org/index.php?title=EcuFlash

 

I haven't the occasion to try it but it did look neat.

 

Interesting to hear about Toyotas problems with their drive by wire Prius.

A situation where ABS and regenerative braking were overriding actual braking (I guess).

 

I heard on the news that it may turn out that the gas peddle issues they are having with their other cars are not mechanically caused but via the CPU!

They have already a firmware fix for the prius but it has also been rumoured that there will be no such fix available for the gas pedal issue.

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