Misfiring 07 3.6

[Nayev72]

we have an 07 VE with 135,000km, battery died so I replaced it. Everything worked fine until the next day when it developed a bad misfire on cylinders 1,2,4 & 6. I replaced the coils and plugs and the misfire was still there but now cylinders 2 & 6. Disconnect the battery to see if that would help. Now it’s throwing P0016 and P0018 crankshaft position correlation faults and now misfiring on 1,2,4 & 6. What’s my next step?

 

[greenacc]

Was the engine making any bad noises before the codes appeared? Could be CAS fault maybe, but do a thorough check over the whole engine for broken vacuum hoses, loose wires, damage etc. If you're lucky it will be something simple that's loose or a rusty earth wire where it's screwed to the body.

 

[Nayev72]

Before I changed the battery it was just fine

 

[greenacc]

Did anything go wrong when you changed the battery? And have you checked the voltage of the new battery because it might be defective. You can check the voltage on the dash in engineering mode.

 

[Nayev72]

New battery is fine