Hi Everyone,

Thank you for taking the time to read this.

Issue: Code P1305 - Bank 2 Cylinder Igniter Malfunction

A mechanic diagnosed my car with a blown head gasket and recommended using a head gasket sealer, my car has 243k-miles. However, I'm skeptical about the diagnosis as I suspect the issue may actually lie within the wiring harness. Swapping out the ignition coil and spark plug did not resolve the problem. I attempted to replicate the same code on cylinder 1; however, it only occurs when the harness is disconnected from the ignition coil, not when the harness is attached to the ignition coil but removed from the cylinder.

I'm unsure how to test for harness damage. I found that two out of the four pins on my multi-meter show a reading of approximately -12, which aligns with the working cylinder.

I'm not sure what to do next. The car continues to run, albeit roughly and with reduced power. Can I continue driving it until it fails completely? Should I consider selling it, scrapping it, or trying to get it fixed? The car ran flawlessly before this issue.

Your advice is highly appreciated. Thank you!

Something does not line up here...according to the DTC listed in the site sticky...P1305 is not valid for a LS430. That code could apply to a LS400, which has one coil for each bank of 4 cylinders. But the LS430 has individual coils for each cylinder. If a coil went bad on a LS430 it would give a code for the faulty cylinder, the codes would be P0351 (coil #1) thru P0358 (coil #8).

That is interesting, maybe I need to buy a new scanner.

So far I've tested spark plugs, coil, harness, cam sensor, now I need to test the crankshaft sensor, if that's ok I'll check the ECU connection last.