2004 S60 ECM-4801 Cat. Faulty Signal. includes waveform

[quietcoolone]

What is missing here is the ECM info on the various times it is monitoring for catalyst performance other than steady load cruising. I have had many vehicles with catalyst codes that would set codes on throttle release based on viewing the frozen data (low throttle but high road speed as in reducing throttle once you have crested a hill) and others that would detect the fault idling.
I have an aftermarket low restriction catalyst on my R and it is not a great performing catalyst based on oxygen sensor signal monitoring alone but the ECM is happy with it and has never set any catalyst codes.
When your cleared the code(s) on your car was there a pattern to when the light would come again?

The one constant is CEL would come on between 50 and 75 miles after reset.

[quietcoolone]

If you partially take the second sensor out of the flow that will probably lower switching frequency, hence no fault code trigerred. Sounds like a cat...

i agree.

[xHeart]

Informative thread!

ECM 4801 has returned on our 2001 V70XC, three weeks after replacing both HO2.

VIDA DTC shows...
Yellow Dot - ECM 4801 - Two Way Catalytic Converter (TWC), incomplete performance check.

The fault tracing points to four possible Intake and exhaust vacuum leaks, and 5th is TWC permanent fault.

I am suspecting TWC too.
Unless there is more to check on VIDA.

[quietcoolone]

Informative thread!

ECM 4801 has returned on our 2001 V70XC, three weeks after replacing both HO2.

VIDA DTC shows...
Yellow Dot - ECM 4801 - Two Way Catalytic Converter (TWC), incomplete performance check.

The fault tracing points to four possible Intake and exhaust vacuum leaks, and 5th is TWC permanent fault.

I am suspecting TWC too.
Unless there is more to check on VIDA.

what are your fuel trims?

[xHeart]

Informative thread!

ECM 4801 has returned on our 2001 V70XC, three weeks after replacing both HO2.

VIDA DTC shows...
Yellow Dot - ECM 4801 - Two Way Catalytic Converter (TWC), incomplete performance check.

The fault tracing points to four possible Intake and exhaust vacuum leaks, and 5th is TWC permanent fault.

I am suspecting TWC too.
Unless there is more to check on VIDA.

what are your fuel trims?

I will check and post.
Where are you with TWC replacement?

[quietcoolone]

i never replaced the Converter. On that car i used a spark plug fouler to move the sensor back from stream.
So far (after about 2K miles) no more CEL.

[xHeart]

From 2/14/2015...
A month after new H2O, and MAF sensors.

I do not know what these number tell us.

Extended View - ECM4801: TWC Efficiency

[vtl]

ECM 4801 has returned on our 2001 V70XC, three weeks after replacing both HO2.

OE sensors or universals?

[xHeart]

ECM 4801 has returned on our 2001 V70XC, three weeks after replacing both HO2.

OE sensors or universals?

Two BOSCH as seen here http://www.ipdusa.com/prodtype.asp?CAT_ID=994&numRecordPosition=0&categorycrumbs=988

[vtl]

I've heard many times that on these P2s you need to use OE oxygen sensors, since others throws errors.