EML

[chris goldson]

Hard to believe but after all my previous troubles now covered over 1000 miles trouble free with new main cat, and now EML light on again. Same reading of cat inefficiency. Incredible !!

Just wondering if it is possible to bypass the two pre cat sensors to start with to isolate them and I understand there is a wiring mod to achieve this but does anyone know of who can supply modified wiring to achieve this.

If not it is back to the sensors once again and reading previous articles it seems that most are only fitting denzo items. Again does anyone have a view on these and where I can get the three items (2 pre cats and 1 main) as probably a good place to start now that the cat has been replaced and problem far less frequent than before.


Best Wishes


Chris

[Ardent]

Have you read the code just to confirm o2 sensors.
to source.
sparkplugs.co.uk
amazon
i fitted denso. Fit n forget.

[1979scotte]

Have you read the code just to confirm o2 sensors.
to source.
sparkplugs.co.uk
amazon
i fitted denso. Fit n forget.

As above.
Worth the money just to save hassles.

[chris goldson]

Had a reply from "sparkplugs" but they require part numbers which I don't have.

[chris goldson]

Code says "cat efficiency below threshold bank 1" but sensors and cat now replaced so wonder if replacement sensor is up to scratch

[Wabbitkilla]

That code is generated by the third O2 sensor which is in the pipe after the main catalyst ... not the ones in the manifold.

[Jon_G]

So could be the cat then? Was it a cheap aftermarket? Has the car passed an MoT since fitting it?

[chris goldson]

Emissions have been checked and reading perfect and car goes well too. Yes it was aftermarket cat has anyone out there got a genuine Toyota one that I can purchase to try?

[chris goldson]

That code is generated by the third O2 sensor which is in the pipe after the main catalyst ... not the ones in the manifold.

Thanks I thought the Bank 1 reading was associated with the pre cat sensors?

[Wabbitkilla]

That code is generated by the third O2 sensor which is in the pipe after the main catalyst ... not the ones in the manifold.

Thanks I thought the Bank 1 reading was associated with the pre cat sensors?

It's a generic code, hence the sensors....
Bank 1 Sensor 1 = Right hand side of manifold ...Part code DOX-0204
Bank 2 Sensor 1 = Left hand side of manifold ....Part code DOX-0204
Bank 1 Sensor 2 = Post cat sensor ..................Part code DOX-0206

So if you're getting cat reading under efficiency and emmissions test show it's ok then B1S2 is running out of life, and they do fail over time.

[chris goldson]

Many thanks for this. Is the B152 the post cat one as this was replaced but don't think it was with a denzo part

[Wabbitkilla]

Many thanks for this. Is the B152 the post cat one as this was replaced but don't think it was with a denzo part

Bank 1 Sensor 2 = Post cat sensor ..................Part code DOX-0206

[PhilzMR2]

Many thanks for this. Is the B152 the post cat one as this was replaced but don't think it was with a denzo part

He said B1S2 not B152. i.e. the post cat sensor, bank 1 sensor 2.

This failed on my car too and caused the EML to come on. Fitted a Denso from sparkplugs.co.uk and all has been well since. It's an easy enough job if you remember to buy an oxygen sensor spanner.

[chris goldson]

Problem is "sparkplugs" are saying I have to "cross reference from the OE part currently installed or as advised by a Toyota main dealer"

[The Other Stu]

Problem is "sparkplugs" are saying I have to "cross reference from the OE part currently installed or as advised by a Toyota main dealer"

As someone above said - DOX-0206 is the Denso part number.
(FWIW, DOX-0204 is the other two)
http://www.sparkplugs.co.uk/denso-oxygen-sensor-dox-0206

[chris goldson]

Many thanks.

Still searching for a genuine Toyota Cat as might change that as well at same time

[Jon_G]

Many thanks.

Still searching for a genuine Toyota Cat as might change that as well at same time

That might be expensive! If your emissions are ok, you might be better fitting one of these (this one is just an example, make sure you get one that fits!)...  m http://www.ebay.co.uk/itm/UNIVERSAL-EXH ... SwkZhWTcbz m

If you have an obd2 reader that can give real-time data then you should be able to tell if the post cat lambda sensor is working by assessing the variability of the output data. Maybe the problem is that sensor?

[Carolyn]

If the emissions were tested and good, the cat is working.

[chris goldson]

Just spotted another cat on ebay which says Toyota 12209 Sango, does anyone know if this is a genuine Toyota cat and if it will fit my 2006 MR2. Anything worth a try to put the light out !!

[Jon_G]

Just spotted another cat on ebay which says Toyota 12209 Sango, does anyone know if this is a genuine Toyota cat and if it will fit my 2006 MR2. Anything worth a try to put the light out !!

Contact the seller and ask for the part number?

However, if the emissions are OK then it doesn't seem worth the expense and cost of replacing the cat. Either it is a poor post-cat lambda sensor OR the current cat is functional but inefficient, in which case an aporopriate sensor spacer may be a more cost-effective fix.

What code are you actually getting?

[The Other Stu]

Might be worth having a read of the Lambda / O2 sensor thread.
The heating circuit is well known to be a bit duff. Perhaps putting a resistor in might fix?

[chris goldson]

Just spotted another cat on ebay which says Toyota 12209 Sango, does anyone know if this is a genuine Toyota cat and if it will fit my 2006 MR2. Anything worth a try to put the light out !!

Contact the seller and ask for the part number?

However, if the emissions are OK then it doesn't seem worth the expense and cost of replacing the cat. Either it is a poor post-cat lambda sensor OR the current cat is functional but inefficient, in which case an aporopriate sensor spacer may be a more cost-effective fix.

What code are you actually getting?

Not sure about the code but will ask. I have not heard of a spacer how would I do this?

Thanks for your help


Best Wishes


Chris

[Ardent]

Well worth getting a code reader. Not expensive and will pay for itself first time you use it.

[Jon_G]

Just spotted another cat on ebay which says Toyota 12209 Sango, does anyone know if this is a genuine Toyota cat and if it will fit my 2006 MR2. Anything worth a try to put the light out !!

Contact the seller and ask for the part number?

However, if the emissions are OK then it doesn't seem worth the expense and cost of replacing the cat. Either it is a poor post-cat lambda sensor OR the current cat is functional but inefficient, in which case an aporopriate sensor spacer may be a more cost-effective fix.

What code are you actually getting?

Not sure about the code but will ask. I have not heard of a spacer how would I do this?

I already supplied an eBay link in an earlier post (you'll need to find one that fits the MR2!). It's an extender that goes between the sensor and the exhaust to reduce sensitivity and is often needed when de-catting to create a pre-cat/post-cat differential reading.

Well worth getting a code reader. Not expensive and will pay for itself first time you use it.

Definitely!

[chris goldson]

Thanks. Yes had a look at the extenders they seem to be 18mm thread which hopefully is the same on the cat. Is there room for a straight one or would I need an angled one to fit?

I don't suppose there is a lot of point getting an expensive code reader