Misfire Code help - What to do next?

[Rs4Fan]

My car developed a misfire when accellerating above 3,000 rpm.

Codes 16685 and 16688 all point towards multiple possible causes. Are there any other dyagnostics that I can run before simply taking it to the dealer?

VIN: WUAZZZ8DZ1N901954
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Address 01: Engine Labels: 078-907-551-AZA.lbl
Part No: 8D0 907 551 K
Component: 2.7l V6/5VT G 0001
Coding: 10711
Shop #: WSC 06435
WUAZZZ8DZ1N901954 AUZ7Z0Y1536103

3 Faults Found:
16891 - Idle Control System RPM: Higher than Expected.
P0507 - 35-10 - - - Intermittent
16684 - Random/Multiple Cylinder Misfire Detected
P0300 - 35-10 - - - Intermittent
16688 - Cylinder 4: Misfire Detected
P0304 - 35-10 - - - Intermittent
Readiness: 0000 0000

Code 16684

Possible Causes
Air Intake System leaking
Fuel Supply faulty
Injector(s) faulty
Ignition Cable(s) and/or Spark Plug(s) faulty
Ignition Coil(s) faulty
Exhaust Gas Recirculation (EGR) Valve (N18) stuck/open
Camshaft Position Sensor (G40) faulty


Code 16688

Possible Causes
Ignition system
Fuel injectors
Fuel pressure
Running out of fuel
EVAP canister purge valve
Evaporative emission system
Low compression
Base engine problems
Controle Module damaged

[TopBear]

Swap the coil packs around to see if the misfire moves with the coil pack.
Check the plugs are tight enough.
Check for vacuum leaks around the SAI system

[Rs4Fan]

Wow - that was quick! I'll try that tomorrow. How do I log MAF readings?

[grizz]

When did you last change the spark plugs ??

[Rs4Fan]

When did you last change the spark plugs ??

Will check - will also check whether they are tight.

Really appreciate the help!

[Rs4Fan]

Turns out I had two bad coil packs. Car runs like a scaled cat again!