Hello, I'm new on this forum, thanks in advance for your time. I've bought recently my first car, a Polo 6N2, 140k km on the clock, the car was kinda fine, just changed few things like spark plugs, oil, oil filter, air filter etc...

A month ago my EPC light and CEL light showed up, and got no throttle response, so I turned off the engine, waited some minutes and car was driving fine again. Recently this EPC light is showing more often, and when I try to accelerate, the RPM drop from 1000 to 400/500, and when I let off the gas pedal they turn back to around 1000, so I got VAG Com and I've found some errors:

 

P0133 - Oxygen Sensor Circuit Slow Response Bank 1
P1196 - O2S Heater Circuit Bank 1 Sensor 1 Electrical Malfunction
P1178 - Linear Oxygen Sensor Pump Current Open Circuit
P1190 - Linear O2 Sensor Reference Voltage Incorrect Signal 
P1545 - Throttle Position Control Malfunction

 

It's possible that O2 Sensor is causing this EPC light? I also noticed that the two pipes from the crankcase breather were not as tight as they should've been and I've heard many times that these 6N2 had a very common problem with throttle bodies... I hope you can help me, and thanks again for your time reading this papyrus 😅

Edited 31 March, 20215 yr by Ale5378

The lambda sensor, or the wires to the lambda sensor could explain any the first four codes.

 

Not sure about the throttle position sensor code - maybe a secondary error.

Very hard to tell without a snapshot of engine load/temp when fault occured.

 

Clear the codes, fit a new or known working lambda sensor, see if it returns.

21 hours ago, dvderlm said:

The lambda sensor, or the wires to the lambda sensor could explain any the first four codes.

 

Not sure about the throttle position sensor code - maybe a secondary error.

Very hard to tell without a snapshot of engine load/temp when fault occured.

 

Clear the codes, fit a new or known working lambda sensor, see if it returns.

Thanks for your reply! I'll try getting a new O2 Sensor, generally the EPC light shows up when the engine is warm 75/80 C°. Could the lambda sensor error be a vacuum leak? Since I saw those pipes from the crankcase breather not in the best conditions... 

When I had an Ibiza with the same engine series, the EPC came on a few times but with no corresponding fault codes and I ended up replacing all the vacuum pipes to/from the inlet manifold and on that engine (AUD code) there was a vacuum valve mounted on the inlet manifold (not the fuel pressure valve) I replaced that as it wasn't operating as per the maintenance manual and the EPC never came back 

 

There are a couple connectors under the thermostat housing on a bracket and that is where the lambda sensor wires go through and it's not uncommon for the pins/sockets too corrode out and often the wires just fall out of the connectors due to the corrosion, so it might be worth a good close look down there before you commit to buying a new sensor 

17 hours ago, nige8021 said:

When I had an Ibiza with the same engine series, the EPC came on a few times but with no corresponding fault codes and I ended up replacing all the vacuum pipes to/from the inlet manifold and on that engine (AUD code) there was a vacuum valve mounted on the inlet manifold (not the fuel pressure valve) I replaced that as it wasn't operating as per the maintenance manual and the EPC never came back 

 

There are a couple connectors under the thermostat housing on a bracket and that is where the lambda sensor wires go through and it's not uncommon for the pins/sockets too corrode out and often the wires just fall out of the connectors due to the corrosion, so it might be worth a good close look down there before you commit to buying a new sensor 

Thank you so much! Today I'll take a look and I hope I could fix the problem 😁