Flashing back to stock after catastrophic engine failure

[Gernby]

Several of the '06+ S2000 owners that I autocross with have all needed to replace or rebuild their cylinder heads over the last year after their valves "sunk" into the valve seats. These are very lightly modded NA AP2's on the factory tune. It doesn't sound like a symptom of an overrev as much as a material defect.

After seeing this happen to so many local S2000's, it has me a bit concerned about my ability to get warranty coverage in the event of a catastrophic engine failure if I'm using a FlashPro. From what I've read, the ECU stores some amount of "freeze frame" data when a catastrophic failure occurs. Do you know what would happen to this freeze frame data if the ECU were returned to stock AFTER the catastrophic failure?

I'm sure that the dealer would do a full data dump of the ECU to see what might have caused the failure, and it would really suck if they immediately knew that the ECU had been tampered with and immediately denied the claim. I understand that the ECU would be reset by the reflash, as if the battery had been disconnected, but would there be any other traces of the reflash?

BTW, I'm not asking about this because I plan to defraud Honda. I just don't want the FlashPro to be an automatic denial of warranty for something unrelated.

[Hondata]

The ECU will store freeze frame data when an error occurs, so you would have to rely on some other error occuring from the valve dropping for the ECU to generate a freeze frame.
I believe the freeze frame data is erased during a reflash (or any power down). However, the over-rev information is retained.

[Gernby]

Hmmm ...

So if my oil pump failed while cruising on the highway, and the engine siezed, the ECU would probably throw a few DTC's, and capture freeze frame data. If I then flashed back to stock, and had the car towed to the dealer, there really isn't a way to know if the dealer will be able to pull the freeze frame data. I would think that would be a huge red flag to them.

Do you think it would be better to just leave the ECU flashed, instead of returning it to stock??

[Hondata]

It's really your decision, but it seems a good idea to leave the ECU alone so that the dealer can read the ECU if they wish - which they may well do if any damage looks like it was from a mis-shift (eg a dropped valve).