Can anyone help with this misfire?

We have changed spark plugs, coil packs and catalytic converter.

 

engine size? can you feel the miss or is it just a code that coming up?

 

it’s the 3.6 L flex fuel V6

Can for sure feel it. It shake horribly and the check engine light flashes. At times it sounds like it is backfiring or a rod is knocking.

I was going to change the fuel injector on cylinder two but have had several mechanics tell me that is the last thing it would be. I’m trying to avoid replacing more unnecessary parts trying to chase down the misfire.

thank you for any help you can offer

 

The fuel trims are way out of wack - bank 2 is running extremely rich (positive fuel trim percentage) compared to bank 1 which is negative (lean). Possible issue with bank 2 upstream O2 sensor. or possible issue with the cylinder head/camshaft (link - https://www.nergersautoexpress.com/b...-we-can-repair)

Why was the catalytic converter replaced? Was it for a p0430, cat inefficient?

Note - use only OEM or NTK O2 sensors, no Bosch ever (do not play well with Chryslers). Denso has been know to work also.

 

it was giving the random misfire and a catalytic converter code so the mechanic told us we needed a new cat, when that didn’t work they suggested spark plugs and coil packs. We decided to fire the mechanic and give it a go ourselves because we are out almost 2000 and the problem is worse.

 

Based on the fuel trims and if it were my vehicle, I would suggest first replacing the upstream (before the cat) O2 sensor on bank 2. Bank 2 is closest to the radiator so the sensor should be fairly accessible.

As a note, replacing the cat for an inefficiency code is typically low/last on the list of items when diagnosing a p0420/p0430 code. A lazy or failing O2 sensor is listed before replacing the cat. On an '06 charger a known failing O2 sensor (heater circuit) triggered a cat efficiency code (P0420 in this case - bank 1). Replacing the O2 sensor cleared both codes.

 

If you pull spark plug 2, what does it look like? The plug should have a tan/gray appearance. A plug running rich would be black. Compare it to the other 2 plugs in the bank, 4 and 6. If injector 2 is leaking/sticking, you should see a black plug 2 and tan/gray on plug 4 and 6. If all plugs are a consistent color it would indicate all of the bank 2 injectors are working as needed.

 

a misfire will some time throw a converter code. the fuel trim is rich because the engine is misfiring the computer is trying to control all aspects of how the engine is running. O2 sensors are doing there job. fuel injector possibly but its likely going to be an internal engine issue aka valve or something.

 

I have the same year as you and had the same problem, turns out it had a bad exhaust valve. I didn't have time to fix it so I took it to Chrysler and they fixed it, but now I have metal flakes in the filter. Not good.