3" Sports Cat - O2 / Lamda Spacer, Yes or No?

[Matt81]

Hi Guys,

Just need some advice as searching the answer has given me conflicting info.

OK so currently running a stage 1 map.  I'm having a 3" DP with Sports Cat fitted this weekend.
I understand the the EML light MAY come on with a Sports Cat.

I'm planning on getting a Stage 2 map at some point but an EML would drive me mad (and could be hiding other issues that arise).  As such I've bought a sensor spacer which is supposed to prevent the EML light to be fitted at the same time.

However I'm getting conflicting answers as to whether the spacer will cause problems with the current map.  i.e the false readings.

Some say the rear sensor only measures but doesn't impact how the car runs while other say it will try to adjust the map incorrectly and cause issues.

Help!

[pudding]

I'm stage 1 with a 3" sport cat and the EML hasn't come on yet.  Some stage 1 maps code out the rear sensor.  Best to speak to who ever mapped it.

[Matt81]

Assuming it wasn't mapped out on my stage 1 (when I had standard exhaust).  What do you think?

Should I get garage to fit the spacer at same time as DP or wait to see if the EML comes on and then fit it (may have to pay small amount of labour)?

Or are spacers just a bad idea in general?  Do they effect anything other than the EML.

[pudding]

Same situation as me.  I had mine stage 1 mapped on a totally standard car, then at a later date I fitted a decat downpipe with a 200 cell sport cat.  My mapper said he couldn't remember if he coded the rear lambda out or not, but I threw the DP on anyway, and so far, no EML.   That was about 3000 miles ago.

Personally I don't like those space things.  The O2 should either do it's job or be coded out.  Personally I would see what happens before fitting a spacer.  Some sports cats are good and don't throw the EML.

Not all cars use the rear o2 sensor for fuel trimming.  I'm not sure what the TFSI's strategy is.  Whether it is purely just for catalyst efficiency checking, or fuel trimming as well, I don't know.  In other words, even with the CEL, it shouldn't affect performance, it's just irritating seeing it on the dash.

[Matt81]

Thanks.

Appreciate the time you took for the above.

I won't give the garage the spacer for now then and see how it goes.

Sent from my SM-N910F using Tapatalk

[c4pete]

Which DPs are you guys using? 

I'm thinking about doing this so any info/feedback appreciated.

[ducman77]

I've got a custom made 3in down pipe with 3in high flow 200cel Magnaflow cat. The cat is wicked cheap at £100 which made me initially a bit suspicious of it but I'm very happy with it!! Plenty of power and no more nasty smell (had a DeCat initially and the smell was awful ). Hope that helps

[pudding]

Mine is an APR downpipe with 200 (I think) cell 'sport' cat.  The exhaust smell from mine doesn't smell sulphury under load and odourless at idle like the OEM cats, it smells rich, so I think the sport cat is pretty crap in terms of catalysing!

[Matt81]

Just to throw me into doubt..

One of the reps form APR is saying that rear sensor is purely a "sniffer" and fitting the spacer will cause no issues.

Tempted again just to get it fitted at the same time (tomorrow).

[Lewo]

I've got a custom made 3in down pipe with 3in high flow 200cel Magnaflow cat. The cat is wicked cheap at £100 which made me initially a bit suspicious of it but I'm very happy with it!! Plenty of power and no more nasty smell (had a DeCat initially and the smell was awful ). Hope that helps

Where did you get that from ducman77?

[ducman77]

The full exhaust was fabricated by a local Exhaust specialist here in Dublin. They do lovely work. You should see the welds
The cat we got from the Longlife website (they use Longlife silencers)
Here's a vid. Hope that helps....