Honda J25 / J30 / J37

The other members of Honda's J-series V6 — the 2.5 J25, 3.0 J30 and 3.7 J37 — in the Accord and across Acura.

The J32 and J35 have their own pages here, and this one covers the rest. Everything below applies to all five: it is one architecture — a 60° SOHC V6 with a timing belt, not a chain.

⚑ The belt is the item that ends these engines, and it catches people out precisely because Honda's four-cylinders of the same era are chain-driven. It is an interference design. On a car with unknown history the belt, the water pump behind it and the tensioner are one job and one decision.

Variable Cylinder Management is the second thing to know, on the engines that have it. VCM shuts down banks under light load, and the well-documented consequence is oil consumption and fouled plugs in the cylinders that spend their life deactivated — plus a vibration through the cabin that owners describe as a misfire. A misfire code on one bank only, on a VCM engine, is a question about VCM before it is a question about ignition.

Motor mounts are a genuine pattern rather than wear, because the active mounts work harder on a VCM car; a shudder at idle in gear is worth checking there early.

The J30Y1 in the Acura hybrids is the same engine inside a hybrid control strategy, so start, charge and idle complaints on one are questions about the system rather than about the engine.