Jespo49

Hey guys, let me give some background. I have an 04 Z with a cat-back exhaust with test pipes and a cold air intake. So this just started happening a little bit ago. When the car is idling you can hear it's not running smoothly like one of the cylinders aren't firing correctly. But when it drives it drives good. Just recently it got worse so when it drives you can clearly hear a cylinder isn't firing.
When this happens the check engine light starts flashing. It's not always like this but it happens. So I took it to AutoZone and checked the engine like and I will attach what it shows.
So it says AFR sensor. It says the sensor could be faulty and that cylinder 3 is running lean. I can replace the sensor but I'm wondering if that's the problem. There is no cat anymore because of the test pipes so I'm wondering will replacing the sensor actually fix it or do I need to get it tuned so the air/fuel ratio is back to normal?
Any opinions on if I should replace the sensor? Will that fix it?
And if I do replace the sensor does anyone know the location of it? It says bank 1 sensor 1.

bealljk

iTrader: (13)

The Downpipe is probably throwing the error code.

this isn’t the easiest thing to do but it’s an old school trick for finding a problematic cylinder -

you’ll want to get the engine started / car running and unplug each wire harness off the coil. What you’re looking for is the cylinder that has no change when you unplug it.

the engine will sound a little different when you unplug the coil harness.

you likely have a cracked spark plug.

I’d replace all 6 spark plugs with a quality plug from OEM Nissan or NGK.

you’ll want to ohm test / resistance check each coil (it’s in the factory service manual)

you should replace the two cam shaft position sensors and crank shaft position sensors with new OEM or Hitachi brand (only)

clean the MAF sensor with maf sensor cleaner.

check for vacuum leaks

do the throttle body re-learn procedure

might be wise to do a compression test too