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Discussion Starter · #1 ·
Hello,

so I’ve been chasing this problem for a while now I have a 330 swapped touring. And I keep getting misfire with fuel cut off on cylinder one, which puts me into limp Mode.

i have done
injectors
Coil pack
Spark plugs
Value cover gasket
Smoke test

but the problem is still consistent. It happens when the car is under load and sometimes at idle.

i got an endoscope and took the best photos of my cats that I could if any one has any tips on this or what could be going on that would be great
Atmosphere Water Liquid Hood Automotive lighting

Water Liquid Window Moisture Snout

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Tints and shades Blazer Circle Electric blue Pattern
 

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If it’s just a single cylinder the cats are fine. You’ve swapped the coil, changed the plug, cleaner/swapped the injector so the next thing is a compression test on all 6 cylinders. Why all 6? You want to see the variation between cylinders. Any difference greater than 10% means there’s a mechanical issue. Also, check the connector on the engine harness for the cylinder 1 coil. Make sure it’s clean and tight. Compare it to the other connectors.
 

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Discussion Starter · #3 ·
So I have done a compression test as well all cylinders are sitting at 170. And yes I’ve swapped the coils all around and I have gotten a new maf and filter
 

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When u say 330 swap? What did u do? I had multiple misfires with fuel cut off after I broke the distribution rail on intake manifold. I bought a used one that came with throttle body. So I just swap all the used parts I bought instead of using what I had. I put my old parts back in now no misfires.
 

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Discussion Starter · #6 ·
When u say 330 swap? What did u do? I had multiple misfires with fuel cut off after I broke the distribution rail on intake manifold. I bought a used one that came with throttle body. So I just swap all the used parts I bought instead of using what I had. I put my old parts back in now no misfires.
From factory I had a 325 but it had bad compression so I took a 330 from a 2004 I havent thought of the distribution rail would that allow it to only be in one cylinder having issues. But I use the car for drifting last time at the track before I got my new maf I used a friends maf and filter and the car ran great so I replaced mine but I’m still having issues
 

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2000 E46 323i, 3.0L, 2.8L and 2.0L Z3's
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Misfires are caused by Electrical and Mixture problems:

Electrical

  • Plugs and coils. Swap with another cylinder to see if fault follows
  • Harness. Dirty connectors, damaged wires, faulty coil earthing resistor, missing coil earth straps (cylinders 1 and 6)
  • DME. Inspect the 2 sets of 6 MOSFETS (Black boxes) around the outside of the DME PC Board for damage. Inspect for PC Board track damage. Any damage will be obvious.
Mixture

  • Too rich. Too much fuel, not enough air. Faulty MAF or Pre-Cat sensor fooling the DME into thinking 1 or the 2 prior causes is happening, blocked Cats, O2 pilot mode on CCV, if the problem is bank specific, a leaking injector.
  • Too lean. Too much air, not enough fuel. Faulty MAF or Pre-Cat sensor fooling the DME into thinking 1 or the 2 prior causes is happening. Vacuum leaks (see first tip)
  • The DME has a performance tune. The DME tables may not match the MAF or injectors fitted. The Air/Fuel tables have been incorrectly altered. Put the DME back to its original tune and see if the problem is fixed.

Your code is indicating an electrical fault.
 
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