Hi. I've had various issues with my vrs in the last few years but for some time now have an intermittent misfire issue at idle and sometime while driving. The car will start up and run but occasionally will misfire so badly that the car wont drive and sometimes just stalls. Also get a bad misfire sometimes if left to idle for a few minutes then if I turn it off it will really struggle to start again.

 

I have checked the fault codes and the one that keeps coming back is p2015 system too rich. When it happens if I clear the code it will be fine again for  bit. Sometimes the code will come back quickly and sometimes will go hundreds of miles without coming back.

 

I've read it could be injectors but surely that would be a constant issue not Intermittent?

P2015 is the intake runner flaps in the intake manifold and wouldn't be connected to the too rich bank 1 code which must be different? How many miles have you ever done decarbon contamination to the intake ports. 2 jobs in one on the table there...

Maybe I've got it wrong about the code. I had the intake runner flaps issue in the past and changed the intake manifold to solve this. Cant remember off the top of my head what the fault code is for system too rich. I didn't clean the valves at the time as I was pushed for time and needed it back together .

P0172 is the code I'm getting for system too rich

49 minutes ago, MARC87 said:

P0172 is the code I'm getting for system too rich

Seems like there is a fault with the new intake manifold then.

 

If replacing a carbon clean will be required.  I've seen how mine looked at 69k miles and it was making mine misfire under light throttle and at idle.

 

Beyond that normal maintenance items should be checked / replaced.  Plugs, airfilter, clean Maf sensor maybe coil packs but usually coil backs would fault under load.

 

PCV fine oils separator can cause too rich / lean codes and is a known failure item anytime after about 5 years.

 

If all the easier items don't solve it then perhaps injectors but again you will have access to those with the IM off and I would suggest sending them off for cleaning and bench testing.

 

 

 

 

The intake manifold was done a few years ago due to the actuator arm failing but it all appears to be good at the minute. Could the maf be the issue? If I unplug it while the car is running there is no change from the engine

My idle problem on gen3 was with camshaft intake magnet.

If you have vcds, tske a look at camshaft adjustment intake bank 1 actual and specified. Specified should be steady and actual not more than +/-2 difference.

2 hours ago, Bingodalton said:

My idle problem on gen3 was with camshaft intake magnet.

If you have vcds, tske a look at camshaft adjustment intake bank 1 actual and specified. Specified should be steady and actual not more than +/-2 difference.

Would usually give a camshaft correlation DTC though?

5 hours ago, TheClient said:

Seems like there is a fault with the new intake manifold then.

 

If replacing a carbon clean will be required.  I've seen how mine looked at 69k miles and it was making mine misfire under light throttle and at idle.

 

Beyond that normal maintenance items should be checked / replaced.  Plugs, airfilter, clean Maf sensor maybe coil packs but usually coil backs would fault under load.

 

PCV fine oils separator can cause too rich / lean codes and is a known failure item anytime after about 5 years.

 

If all the easier items don't solve it then perhaps injectors but again you will have access to those with the IM off and I would suggest sending them off for cleaning and bench testing.

 

 

 

 

02 sensor too maybe suspect. 

3 hours ago, MARC87 said:

The intake manifold was done a few years ago due to the actuator arm failing but it all appears to be good at the minute. Could the maf be the issue? If I unplug it while the car is running there is no change from the engine

When you unplug the Maf while the car is running you should feel a change in engine behaviour otherwise what's the point of it. Check/ clean or replace it. See if any wire are damaged 

Mine did not show any faults, it needs to be way off. 

Just check data.

For O2 it is easy to check too.

If it is narrowband O2 it should fluctuate up and down from 0.2 to 0.7v on idle. This is for first sensor. Bank 1 sensor 1. This means that O2 is switching from lean to rich and back, which is ok. If there is wideband sensor, then Lambda should be arround 1 (0.98-1.02). I do not know for gen2 engines is it narrow or wide.

Sensor 2 should be steady on idle, which means that cat is working. It is narrowband sensor for sure.

When you depress gas pedal shortly, both values should change at the same time.

For both narrowband both should go up together, while for wideband/narrowband should they go opposite way. 

Wideband lambda is bellow 1 rich, more than 1 lean.

Narrowband sensor is 1-0.5v rich, 0.5-0v lean.

 

Edited 14 November, 20214 yr by Bingodalton

9 hours ago, MARC87 said:

The intake manifold was done a few years ago due to the actuator arm failing but it all appears to be good at the minute. Could the maf be the issue? If I unplug it while the car is running there is no change from the engine

If it is still reporting p2015 after clearing he new one has a problem and the ecu won't be moving the flaps in operation. But not the cause of the over rich code. 

51 minutes ago, TheClient said:

If it is still reporting p2015 after clearing he new one has a problem and the ecu won't be moving the flaps in operation. But not the cause of the over rich code. 

I'm not getting the p2015 fault...I just got the codes mixed up

15 hours ago, MARC87 said:

I'm not getting the p2015 fault...I just got the codes mixed up

Ok. That is good. I fear you maybe taking off the manifold again though.  Obviously try the easier things first and even the £80 for a new genuine pcv would be worthwhile maintenance, especially if it has never been replaced.

Does anyone know any places online I can order genuine parts from? 

Skoda maybe ?

 

i tend to always use euro car parts to be fair but failing that then Skoda direct