hi,
I checked my sisters 1.2 2003 polo, engine code AWY with VAG COM as the engine check light was on, it gave the following code that points to the lambda sensor,
16804 - Catalyst System; Bank 1: Efficiency Below Threshold
I was just going to buy a new probe and fit it, but apparently there are two probes on this car. Anyone know if this code refers to pre or post cat sensor?
cheers
mike
lambda sensor
-
RUM4MO
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Re: lambda sensor
Hum, I'd be worried that what is being "said" is that the cat is dying, but which cat? I think that there are a few reports of cat failure already on these 3 cylinder engines. Do you know if you have two cats, ie a manu-cat and then a cat, I don't know which one dies first. It will be the signal from the bank 1 sensor 2 that is giving this info out. Do a search here, seatcupra.net (Ibiza forum) and briskoda.net (Fabia forum) - and see what you find. By the way, are you using "quality" petrol and is the car getting some longish runs, also are the plugs and air filter okay?
In case you don't know, the S1 sensor is a regulator, so if its not controlling the mixture then this might let too much fuel into the engine, the S2 sensor is only a monitor to warn about excessive emissions - which it might be doing!
Probes are quite expensive - about £130 for the front one and a bit less for the rear one, but they do seem to be quite easy to remove with a 22mm spanner - the front one hides behind the manu-cat so is a bit of a challenge to reach - its plug/socket is on the vertical bracket at the front near the gearbox/engine "joint" - there could be two other plug/sockets on that bracket! The rear one's sticking out of the exhaust after the second cat - its plug/socket hides under the O/S plastic full length cover - needs removing, then you need to open a plastic box to find the plug/socket inside.
If the plugs and aircleaner are okay, then maybe try to clean out the EGR valve etc, then maybe try some fuel system cleaner with "good" fuel after that there is always a "cat cleaner".
I've not had this problem as the engine is a 1.4, but the first Lambda probe has failed but VAG-COM clearly identified it as it logged "O2 Sensor Bank 1 Sensor 1" codes.
In case you don't know, the S1 sensor is a regulator, so if its not controlling the mixture then this might let too much fuel into the engine, the S2 sensor is only a monitor to warn about excessive emissions - which it might be doing!
Probes are quite expensive - about £130 for the front one and a bit less for the rear one, but they do seem to be quite easy to remove with a 22mm spanner - the front one hides behind the manu-cat so is a bit of a challenge to reach - its plug/socket is on the vertical bracket at the front near the gearbox/engine "joint" - there could be two other plug/sockets on that bracket! The rear one's sticking out of the exhaust after the second cat - its plug/socket hides under the O/S plastic full length cover - needs removing, then you need to open a plastic box to find the plug/socket inside.
If the plugs and aircleaner are okay, then maybe try to clean out the EGR valve etc, then maybe try some fuel system cleaner with "good" fuel after that there is always a "cat cleaner".
I've not had this problem as the engine is a 1.4, but the first Lambda probe has failed but VAG-COM clearly identified it as it logged "O2 Sensor Bank 1 Sensor 1" codes.