Re: Alarm but no codes?
Not sure how or why corrosion in the midsection would cause only the starboard side to overheat.
But, reviewing these posts, I think this whole discussion is getting out of hand.
* Original problem - you're getting a continuous alarm and engine goes to SLOW mode. You can shut down, restart, and motor runs fine.
* You have a two-light display, and the red light comes on. That could be temperature, PGMFI, or ECM. Did the green oil pressure light stay on?
* You tested the t-states and they seem to be fine. You reverse flushed engine.
* BUT, dealer says HDS did not show any fault codes - overheat or low oil pressure.
* Dealer thought it was a head gastket or warped head, and replaced gasket (and presumedly checked for a warped head), which did not solve the problem.
My observations.....
1. Are you sure you are really overheating on the starboard side? How do you know? HDS should give a code for that. You should be able to place your hand on the head of a warmed up engine, without getting burned. Or use a heat probe. Compare both heads for significant heat differences.
2. If you are not really overheating, then I strongly suspect you have a bad ECM - continuous alarm, goes to SLOW mode, yet EPROM is storing no codes. It should.
3. As Hondadude recommended, swap out the ECM with a spare or loaner.
4. Another possibility is a faulty heat sensor that for some reason the ECM is not recording. Test it by disconnecting and see if alarm goes away.
5. If the starboard side is really overheating, Then I suspect you have a blockage in the cooling system. BUT, HDS should still through off a code, so I still would suspect the ECM PLUS a blockage.