VS 5l manual ute misfiring if revved past 3500 rpm

[3.8VS-UTE]

G'day ive got a vs 5l manual ute which revs out fine to 3500 rpm, but kinda dies off and starts misfiring/running rough for a fewseconds afterwoods, i did a fault code check and came up with
Code 12 - System Pass (OK)
Code 16 - ECT Sensor - Voltage Unstable - Auto Transmission Only

any help would be much appreciated Braeden

[Clint_G]

Is it an auto model thats been converted to manual or is it a factory 5 speed ute

[3.8VS-UTE]

original manual, left oxygen sensor wiring looks like its had a bit of heat, so i un plugged it and went for a drive and it still does it but when i rechecked the codes with it unplugged it still only came up with 12 and 16

[VrWagz1]

Sounds like the dizzy cap or the coil. Or it could be a dodgy lead or spark plug. Check them out.

[BlackVXGTS]

DTC16 is NOT an auto only DTC, it applies to V8 manuals as well as autos. You need to check out the sensor wiring to make sure there are no shorts and/or replace the sensor (around $15 from Holden last time I bought one). However, I can't see that causing your misfiring problem. Agree with VrWagz1 on the leads (especially the coil lead), plugs, cap (and rotor). Leave coil to last as it's a bugger to replace - although if you are replacing the distributor cap you are half-way there.