Misfire Options

[kieronboz]

Hi, my Celica has a bit of an intermittent misfire, mainly its noticeable when cruising if your foot is held steady, at say 2.1k, you can feel the car bunny hopping, when idling still, the misfire creates an occasional blowiness in the exhaust.

Any suggestions around air/fuel im keen to hear as that's what im leaning towards.

One thing we did notice, is the engine definitely sounds 'worse' when this white unit (pictured, I think its idle air valve thing?) is plugged in, however unplugging it didn't resolve the issue, admittedly Idk what you'd expect, unplugging it surely cant help, but anyway I'm looking for a new one of these too.

<a href="https://ibb.co/Pgyh1dd"><img src="https://i.ibb.co/Pgyh1dd/PXL-20231206-115316481.jpg" alt="PXL-20231206-115316481" border="0"></a>

What would you be addressing next?

So far we have changed;
- Rocker cover gasket
- Spark plugs
- HT leads
- Distributor
- Rotor cap
- ECU (used)
- Coil pack (only plugged in and tested, I bought wrong one so it didn't fit to the car, but plugged in?)

Parts on the way;
- O2 Sensor

[Consynx]

You’re on the right track w the O2.

IACV is just that, idle.
Steady throttle is the thing making me think O2, given that you’ve already tackled plugs and wires.