02 probe too high

[Big_daddy]

Ive getting a message from rear 02 sensor. B1:S2 Internal resistance too high. The thing is ive got a high flowing cat. im aware this is causing the issue to bring the fault up. but i want to know. does this

1. effect the performance in any way.?
2. effect the mpg in anyway.?

The info would appreciated.

 

[BeartheBruce]

Could you post the full fault code information for us?

If the oxygen sensor is going bad, it can have effect on performance and fuel economy as the engine controller will try to alter the fuel trim to compensate. Without seeing the full code, all I have said is speculation.

Usually an error about resistance too high is related to the heating element in the oxygen sensor. If heating element goes bad, the sensor will not get to proper operating temperature quickly and may not reach proper temp at all especially given the high flow cat. I would expect the performance issue to be more prominent on a cold engine than on a warm engine.

 

[Big_daddy]

17522 - Oxygen (Lambda) Sensor: B1 S2: Internal Resistance too High
P1114 - 35-00 - -

The rear sesnor is brand new aprox month old. the faults keeps coming back, after i cleared it so many times

 

[Big_daddy]

ive order this fouler that should gap it for me.

http://forums.vwvortex.com/zerothread?id=1366095

 

[Big_daddy]

Could you post the full fault code information for us?

If the oxygen sensor is going bad, it can have effect on performance and fuel economy as the engine controller will try to alter the fuel trim to compensate. Without seeing the full code, all I have said is speculation.

Usually an error about resistance too high is related to the heating element in the oxygen sensor. If heating element goes bad, the sensor will not get to proper operating temperature quickly and may not reach proper temp at all especially given the high flow cat. I would expect the performance issue to be more prominent on a cold engine than on a warm engine.

Im aware if the 1st 02 sensor on the down pipe can effect it, but does this also count for the rear sensor on the cat.

 

[BeartheBruce]

It was my impression - and I am not expert here but I will ask him later - when he gets in - that both were involved in calculating fuel trims.

Seems we also are having trouble finding more info on that fault code. I will continue looking into and hope to get back later today.

 

[goble]

lambda probe heting problem
check fuse number 8
and fuel pump relay is o.k.
evaluate measuring block 41 and check that function is alternating 0-12v alternating.
scope lambda probe

 

[BeartheBruce]

There seems to be conflicting information as to whether or not the post Cat sensor has an effect on fuel trim. There are some documents that say it does and others that say it does not.

As to the resistance fault, we think that if you just replaced the sensor, then likely the fault is a wiring problem. Corroded connection? Break in the wire? Only connecting by a thread?

Might be a bad ECU where the ECU is not able to properly measure the heater resistance value. Not likely by the way - but certainly possible.

 

[Big_daddy]

It was my impression - and I am not expert here but I will ask him later - when he gets in - that both were involved in calculating fuel trims.

Seems we also are having trouble finding more info on that fault code. I will continue looking into and hope to get back later today.

Well the post sesnor supppoose to think the cat is doing its job, but due to high flow cat, it thinks theres too much fumes flowing.

 

[Big_daddy]

lambda probe heting problem
check fuse number 8
and fuel pump relay is o.k.
evaluate measuring block 41 and check that function is alternating 0-12v alternating.
scope lambda probe

well fuse 8 states to be a telephone device (according to manual).

here block readings 041

 

[BeartheBruce]

From the screen, you can see that the ECU cannot calculate the post cat sensor heater resistance. I still think you have a connection problem since you told us that you replaced the O2 sensor recently.

Look at the third block. It should have a value shown there. The controller is turning the heater on but it cannot measure a value for the heater element in the O2 sensor.

 

[Big_daddy]

Ive checked the connectors and then double checked it, the thing was i should have waited abit for respone. but now its coming up. BUT im still getting the same FAULT after i cleared so many times.!

 

[BeartheBruce]

The only other question I have is if the sensor you replaced is the exact same part number. I think the ECU is looking for the resistance of the heater to be about the same as is for the Pre-CAT sensor. You can see from the numbers that the Post-CAT is at 2.5kohms and the Pre-CAT is at 100 ohms (0.1Kohms) That is a huge difference.

Sorry I don't what value should be there but I would expect for the heater to work properly, it should be similar to the Pre-CAT sensor. Maybe someone who has a Leon 1.8 20VT could post their readings for you.

 

[Big_daddy]

Well GSF parts gave me,
is this could be because of the high flowing cat?

 

[goble]

I would try a genuine part and go from there to be honest.
you really want to be checking all your feeds and earth's are correct at the connector an scope the wave pattern of the probe which should be alternating rich lean rich lean etc.
if this is not ok then i would try checking the resistance between the probe and ecu with the ecu disconnected to eliminate a wiring problem
The second probe just confirms that fuel /air ratio is correct but does not alter the ratio at all as well as checking cat efficiency
probes can be checked as well as cat efficiny by using 15 readiness codes (if vag com has this function)
have you had the gas output analysed??(4 gas analyser)
if tall of the above are o.k. try your old cat
if the problem persists then its going to be a new ecu

 

[Big_daddy]

Ive just added the fouler to sensor which gives abit of gap. but now i ve got his fault coming up instead. !

VAG-COM Version: Release 303.1

Control Module Part Number: 06A 906 032 T
Component and/or Version: 1.8L R4/5VT 0003
Software Coding: 05510
Work Shop Code: WSC 00000
1 Faults Found:
16522 - Oxygen (Lambda) Sensor B1 S2: Signal too High
P0138 - 35-00 - -

 

[Big_daddy]

Got it sorted now. replaced the lambda sensor. Thanks guys.
Here are the results.