Codes P0171, P0174, P0313, P1349 /BMW 330i E46 160K Engine slightly misses when first starts but as it warms up it runs very rough idle and misses but no backfires. Increase RPM and have less roughness but still has missed fires. Changed spark plugs right off its been 50,000 miles since last change but they look relatively clean no excessive carbon build up. Checked Coils and Ohms resistance on all 6 are ~ 1.5, No cracks/leaks in air intake boot etc. I do have a cold intake by Dinan but have had it for over 6 yrs no issues. O2 intake/sensor all clean.
P0171 Fuel trim lean Bank 1
P0174 Fuel trim lean Bank 2
P1349 Multiple misfire
Having a lean condition , somehow you are getting vacuum past the MAF (mass airflow) the PCV can be taking in vacuum at idle it PCV hose connection can have a leak
This is just one of its PCV hose connection check the lines for any leakage, P1349 usally id due to a faulty PCV valve.
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