It looks like you're new here. If you want to get involved, click one of these buttons!
Honda Odyssey Engine Ping, Detonation, Preingition issues
It's definitely not " normal ". My van (07 Touring) does it on initial acceleration, just before and after the vans shift points at 50km/h(30mph) and 70km/h(45mph) under light acceleration, and up hills especially when the engine is hot.
The knock sensor is supposed to prevent this from happening.
The problem is real! Honda Canada and my dealer said, after working on it for 3 weeks, that it is indeed a pre-ignition/ detonation noise. They don't no why it's doing it, and they don't know how to fix it!!!!
The problem is defined by Wikipedia in 2 ways but the result are the same :
Knocking (also called pinging)-
Colloquially detonation—in internal combustion engines occurs when air/fuel mixture in the cylinder has been ignited by the spark plug and the smooth burning is interrupted by the unburned mixture in the combustion chamber exploding before the flame front can reach it. The engineered combusting process ceases, because of the explosion, before the optimum moment for the four-stroke cycle. The resulting shockwave reverberates in the combustion chamber, creating a characteristic metallic "pinging" sound, and pressures increase catastrophically. It can range from hardly noticeable to complete engine destruction.
Detonation or pre-ignition-
The fuel/air mixture is normally ignited slightly before the point of maximum compression to allow a small time for the flame-front of the burning fuel to expand throughout the mixture so that maximum pressure occurs at the optimum point. The flame-front moves at roughly 33.5 m/second (110 feet/second) during normal combustion. It is only when the remaining unburned mixture is heated and pressurized by the advancing flame front for a certain length of time that the detonation occurs. It is caused by an instantaneous ignition of the remaining fuel/air mixture in the form of an explosion. The cylinder pressure rises dramatically beyond its design limits and if allowed to persist detonation will damage or destroy engine parts.
Consequences of Knocking or Pre-ignition
Engine knocking has disastrous consequences for the engine, since it leads to the catastrophical wear of the combustion chamber walls, through particle wear for moderate knocking, to welding for serious knocking. This is due to the contact between those walls and high temperature gases resulting from the unwanted explosion. The processes also lead to a 'knocking' noise for the engine, that give its name to the phenomenon.
A big problem us owners are having is finding enough of us to recognize our vans have this problem and to make Honda do something about it - I think they should buy the vans back and do the research on them that is required to fix all of them.