I was given a Honda Ridgeline with a check engine light to diagnose. It came up with two codes, one current and one pending. The current code was P219A AF Ratio Variation of Cylinder, which on Honda Pilots and Ridgelines leads to replacing the fuel injectors. The pending code was P0304 Misfire Cylinder 4. I didn’t pay much attention to the P0304 because it was a possible additional code that can be triggered by the same condition that throws the P219A. When I got to replacing the fuel injectors, I found another problem.

It’s common to find small animal nests under the engine cover on the top of the V6’s found in Pilots and Ridgelines, but when I got the intake off and was down to the fuel rails, I found another nest, where I never have before. I figure that even though it’s in a spot I don’t usually see nests, it’s not a problem, but when I removed the fuel rails, I found that the animal nesting there had gotten hungry. What it chose for a snack was the insulation on the wiring going to the fuel injector in cylinder 4. While the P219A code did correctly point to replacing the injectors, the P0304 code was caused by the injector wires shorting.

Because the wiring insulation was merely chewed off and the wire wasn’t chewed through, I could’ve just wrapped some electrical tape around it and called it fixed, but with how deep it was under the intakes and fuel injectors, I went with the safest route and replaced the harness. Luckily for the customer, it wasn’t a whole engine harness, just a sub-harness for the front bank of cylinders,. so it wasn’t too expensive.

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-Dan