Hey guys,
Registered my BA Ute a month ago, when I first started driving it would misfire at 2500RPM. Fixed that problem with new plugs and coils, after about a week the car started to gain a very slight misfire again and after a few days the car struggled to start was nearly stalling at idle and stalled when taking off if you didn't plant your foot into it. The car is running very rich and even when it was running OK I only got 430ks from a tank.

Here is a list of attempted fixes:
Coils
Plugs
O2 sensor
Intake manifold gasket
Injectors
Stainless Fuel rail
Blown out the fuel lines
Fuel pump
Fuel filter
Fuel Regulator
MAF sensor
Had the car scanned no codes other than running rich

I've been in touch with several mates who are mechanics and they are a bit stumped as well. Hopefully, someone has some ideas of what to try next.

Cheers guys.

UPDATE:
Pulled the Plugs and they were black. Cleaned them and put them back in, car ran great for a little while, after half a tank of petrol I started to notice the misfire return at 2250RPM, exactly what it was like before it got the underivable misfire I explained earlier. I think this has narrowed the problem down to fuel delivery as the car is getting 400ish k's to a tank, unless that is the normal range then Im thinking that for some reason it is overfueling.

Thoughts?

Last edited by Bionic_Tonner on Wed Aug 03, 2022 5:32 pm, edited 1 time in total.

That's a tough one... Maybe the PCV Valve, or a clogged Catalytic Converter...