Cars

VW Golf Error codes 16684 and 16685:  Missing on cylinder 1 – And subsequent 16804 Error Code

Error codes 16684 and 16685:  Missing on cylinder 1

16685: Cylinder 1 Misfire Detected
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 

Special Notes: This feature search for engine misfire in a specific cylinder. Most of the time the cause for a misfire is a lack of combustion in a cylinder due to absence of spark, poor fuel metering, or poor compression.

16684: Random/Multiple Cylinder Misfire Detected

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 

Possible Solutions

* Check Misfire Recognition
* Check Air Intake System
* Check Fuel Supply
* Check Injector(s) and Injector Sealing
* Check Ignition Cable(s) and Spark Plug(s)
* Check Ignition Coil(s)
* Check Exhaust Gas Recirculation (EGR) Valve (N18)
* Check Camshaft Position Sensor (G40) 

Many times after popping the misfire codes the car would also pop a P0420 Catalyst System,Bank1 Efficiency Below Threshold 16804.  It appears that the extra stray gases from incompletely burnt gasoline is more than the catalytic converter can handle. Most of the time this code is popped is after a misfire code but I have finally seen it with no misfire code.  However there seems to be a residual misfiring so perhaps the engine is misfiring below the threshold that pops the misfire code.  

Next debug step:  use a spray bottle to mist around the ignition coil and the plug wires to see if I can exacerbate the misfire problem.

Resolution:

  • Spark plugs had a lot of wear.  I suspect they had never been changed on this car as of 92kmiles.  Replacement resulted in the misfire codes not returning.  See photo below.  This cleared most of the problem. 

eroded spark plugs

By Fudgy McFarlen, ago

Ford Econoline 150 Van Radio Refit

Commercial radio is full of commercials and the content is lacking.  I need a digital media capability so I can listen to podcasts.

This effort has superceded by the:  Icarus CarPi CarBerry – CarPuter Informatic Devices to Replace your car radio  process.    It will end up being more flexible and expandable.  Monitors CAN bus of the car too.

Research Links

By Fudgy McFarlen, ago