I changed the timing belt, checked all the coil packs, put in new plugs, and even replaced the injector in cylinder 5, but I’m still getting a code 305. The engine has a slight miss at idle, but it seems to go away when accelerating. There’s no noticeable engine noise, just the miss.
Any ideas on what could be causing this?
Despite the thorough maintenance, the persistent code 305 and idle miss in cylinder 5 remain a mystery. While the miss disappears when accelerating and there’s no noticeable engine noise, it’s perplexing. Check the fuel injector wiring and compression in cylinder 5 for potential issues. If the problem persists, consulting a professional mechanic with diagnostic tools might be necessary.
After my TB change, I was still using that code. It was the fragile harness connector, as it turned out. Things are rearranged. Two cylinders are affected by a coil. It is feasible to use a wire. Even with broken interiors, they can still appear to be in one piece. I doubt it’s the ICV if it didn’t have the code prior to the TB change. But anything is conceivable.
You’ve covered a lot of ground already, which is impressive. A code 305 usually points to a cylinder 5 misfire, but since you’ve replaced the injector, the issue might lie elsewhere.
It could be a faulty spark plug, even though you replaced them, or a problem with the wiring to that cylinder.
A compression test could pinpoint if there’s a mechanical issue like a burnt valve.
Have you checked the fuel pressure regulator? Sometimes, a faulty regulator can cause fuel delivery problems to specific cylinders.
Also, consider inspecting the catalytic converter. A clogged converter can restrict exhaust flow and contribute to misfires.
It might be time to bring in a mechanic with a cylinder leak-down test to really dig deep.