It is Honda's turn to handle head gasket problems on new dual motor hybrid design introduced in 2023. https://www.go-parts.com/garage/engine-cylinder-head-honda-civic-honda-accord-honda-cr-v-2023-2025?srsltid=AfmBOoqm5I38lGu-zCmkyKWlZopEBI74YjciMM21KhzpyossbcTy9tke
it amazes me that these geniuses can't get it right. it must be the bean counters, the engineers can't be this bad
It's the first twin electric motor for Honda who did not license Toyota technology likeFord did. Thermal cycling that was not present in Otto port injected versions of the engine is the likely cause as is the most logical case with gen3.
They went from a naturally aspirated engine to a direct inject; turbo charged engine. Engine start/stop systems probably compounds matters. Higher pressures and heat spots contribute to the issues along with customers that have a closed hood policy. I'm paying someone to maintain the car; so I don't need to check anything. Just my take on things. They're making it out of the warranty period, just doesn't meet customer expectations; which are very high - considering the cost of new cars these days.
It isn't their first power-split hybrid system. It first showed up in the previous generation Accord and the Insight3. And Toyota licensed Ford emission controls that they really wanted. The reality was that Ford developed their system independently. Toyota just beat them to the patent office. And they both ended up paying Paice. No turbo in the hybrid. "The primary cause is suspected to be the frequent on-and-off cycling of the gasoline engine in a hybrid system. This repeated heating and cooling (thermal cycling) puts significant stress on the head gasket, potentially causing it to fail much earlier than expected." Guessing the direct injected engine that showed up in the 2023 Accord runs hotter.
