Hi there !

 

I have a 2011 Fabia vRs with 84000km, since last November. Until recently everything was fine with the engine except for slight oil consumption (~0.3L/1000km).

 

As spring is really on its way I have noticed that the engine is not running smooth after starting when it's about 20+degC outside. This lasts about 30 seconds of driving, then it settles itself. What is strange here is that this does not happen bellow 15degC outside.

 

Typical example is, leaving for work at 7am 10degC outside, all is fine. Leaving from work, 6pm 20+degC outside, engine unstable for the first hundreds meters ...

 

I have never experienced any misfire under load or anything. No fault code on my OBD reader (Torque + OBD plug). Plugs were changed at 70k km. 

 

Any thought on that ?

 

Could it be that ECU is not using the correct enrichment map and it settles when lambda closed-loop controller kicks in ?

 

Thanks

Woland

Which country are you in?

 

Maybe the spark plugs need changed again, probably not though.

What plugs went in, and did you do them or someone else.

Maybe get the latest Software Update on the ECU as well.

 

Misfires often do not show as a code if there are not enough in any cycle.

 

It can just be Heat Build up in the Standard Airbox that has it run unstable for the first start up.

Is there a fresh / clean Air Filter in the Air Box?

Suspect Coolant Temperature Sensor, injector fault, bad spark plug or (lead or coilpack as applicable): definitive diagnosis would need codes read.

No codes show in the various instances of this on a 1.4 TSI Twincharger.

 

When there are codes it commonly is,

Misfire cylinder 3, and Skoda Assist in the UK say Coil, when it is the plug, 

Low Fuel Pressure, and Air Intake Pressure.

 

How you drive before parking up can mean the 1 spark plug is sitting a little Oiled up (or in a sooted up state.)

Hot Air in air Box and oiled spark plug cylinder 3 gives an unstable start up.

 

Not that big a deal really as a Twincharger Engine gets older as long as it does not start burning out that plug.

Which country are you in?

 

Maybe the spark plugs need changed again, probably not though.

What plugs went in, and did you do them or someone else.

Maybe get the latest Software Update on the ECU as well.

 

Misfires often do not show as a code if there are not enough in any cycle.

 

It can just be Heat Build up in the Standard Airbox that has it run unstable for the first start up.

Is there a fresh / clean Air Filter in the Air Box?

 

I'm in France (Hell, a bloody French !)\

 

The plugs were changed by the Skoda dealer before I bought the car, I don't know what they were changed for. Most probably OEM parts.

The car had the 90k km maintenance done two weeks ago by Skoda dealer (oil changed for 5W40 at my request, air filter, brake fluid), no ECU update required apparently.

 

I have discussed with a colleague (gasoline engine engineer) who tells me that VW has quite aggressive Cat heating strategies with quite rather bad drivability. This plus air temp error (in the sun all day), plus (most probably) open-loop lambda control, he was not surprised by the result.

 

I will check next time when does closed-loop kick in.

Apparently is not good enough, ask again.

 

There is a Updated Spark Plug now that VW List.

 

Lots of cars start and run smoothly at 20*oC start up when using the Prescribed 98 ron or higher octane.

So the ones not are not because they are expected to.

The Aggressive Cat heating stuff is an oft mentioned load of bull.

 

Be aware when you open the drivers door the Fuel Pressure is primed if the car has sat a while.