Redex - Pre MOT to help lower emissions?

[M@tt_182]

Every year my car seems to fail on emissions despite replacing various sensors. It's had a replacement CAT around 3 years ago so I'd also like to think that's ok.

I was wondering about dumping some Redex in this weekend and booking it in for Monday. I'm not sure this will make a difference but must be worth a go?

I suppose I'm hoping it'll pass but what would be the next steps if it fails again? Also it only ever fails by a small amount.

 

[Harbinger]

You doing the MOT on a hot engine, such as ragging it before the MOT, Cleaning the Cat out @7000RPM and 1000c?

 

[M@tt_182]

Last year the garage had it for 2 days which consisted of spirited drives on the ring road and then testing. It helped to lower the emissions a little however it was still just failing. I'm not wanting to fork out for a new CAT however it seems like this could be the last resort if it fails next week.

 

[Saul]

I think putting redex in for a series of weeks may make the difference if any!? I always throw it in anyway

 

[Robiniho77]

New garage?

It shouldn't be failing with a cat from new let alone a 3 year old one.

Are they reputable? Specialist? Halfrauds auto centre?

Might just be picky..

 

[Saul]

Actually has the car been re-mapped?

But yeah as above maybe try elsewhere!

 

[Chip-mk1]

I dont think redex is likely to make a difference by the sounds of it you just have a cheap replacement cat that isnt very efficient?

But it depends a bit which emission test its actually failing on?

 

[Fred@BTM]

take it to my MOT man, it'll pass

 

[Harbinger]

Changed plugs and leads prior to this? just to get it burning as clean as possible, I reckon an RStuner would help a lot, makes it run so much cleaner, my emissions were really good last time ( everything else was fucked though )

 

[Chip-mk1]

Its held at 3K at part throttle for the cat test, I dont see how an rs tuner will effect this, its on lambda control either way!

 

[Harbinger]

I just thought it made it run better as a whole, Surely better economy means more efficient fueling and thus cleaner emissions? although probably being a r****d here as I do have no idea how these things actually work

 

[Chip-mk1]

I just thought it made it run better as a whole, Surely better economy means more efficient fueling and thus cleaner emissions? although probably being a r****d here as I do have no idea how these things actually work

The standard car and the RS tuner one both run the same fuelling at part throttle at the point that the test is conducted mate. Its only one very narrow bit of the map that gets tested.

 

[Harbinger]

Oh right I see, I remember this coming up a while ago when you say that, same way pops and bangs crap doesn't affect it as under 4k. I will stay out now.

 

[Dr HMS Derv Destroyer]

The guy I use for MOTs puts a cap full of this stuff into car oil if they don't pass. It somehow passes after that. Go figure...

Take it Fred's MOT guy.!

Usually aswell, if the filters on the emmisions machine is dirty it will make the reading higher

 

[M@tt_182]

I'm pretty sure it's a cheap replacement as it only cost aprox £200, this was fitted prior to me buying it.

It's been mapped with an RS Tuner a while ago however I think that was after it's last MOT.

The garage I use is a local one that's MOT'd the family's cars for years so I trust them. The lad who works there spent hours tinkering with it so it just passed. Ideally I'd like to find the problem however a friendly MOT could end up being the answer.

 

[Maccy]

The guy I use for MOTs puts a cap full of this stuff into car oil if they don't pass. It somehow passes after that. Go figure...

That sounds like a trust worthy place

Matt, have you tried changing either of the lambda sensors?

 

[M@tt_182]

That sounds like a trust worthy place

Matt, have you tried changing either of the lambda sensors?

I changed one last year (pre CAT?), the garage also did some tests swapping them around and it still made little/no difference.

 

[r0ss172]

You can always use my CAT just to get it through the test if needs be?

 

[The Fatty]

just to give you an idea, my 182 with original cat + RSTuner map passed just last week with these results:

engine speed: 2000-3000rpm
CO : 0.001% (limit 0.2%)
HC: 0ppm (limit <=200ppm)
lambda: 1.028 (limit 0.970-1.030)

 

[M@tt_182]

It's going in on Monday to check the emissions before it get's MOT'd. I'll update with results then.....

 

[Chip-mk1]

just to give you an idea, my 182 with original cat + RSTuner map passed just last week with these results:

engine speed: 2000-3000rpm
CO : 0.001% (limit 0.2%)
HC: 0ppm (limit <=200ppm)
lambda: 1.028 (limit 0.970-1.030)

That CO and HC dont seem realistic at all to me, did he yank the probe out for those tests?

 

[The Fatty]

That CO and HC dont seem realistic at all to me, did he yank the probe out for those tests?

It might be possible the test didn't actually run on those I suppose? Just looked at my printout for the 100TCE and it shows the same for those two. I didn't see any probe yanking (thankfully).

 

[M@tt_182]

It failed on the lambda reading, not sure by how much but all other readings are OK. It had a replacement sensor last year, is it worth changing it again? What could be another reason for it failing on this?

 

[Chip-mk1]

New lambda sensor is probably a good shout.

It could also be the CTS though, as it wont start using the Lambda till its upto temp.

 

[M@tt_182]

Oh ok, would I see any sign of the CTS failing or is it not something that breaks as such?

 

[Ryanj]

What about getting it terracleaned? apparently this can vastly reduce emissions, dont quote me on this, its not something I've ever done myself

 

[Chip-mk1]

What about getting it terracleaned? apparently this can vastly reduce emissions, dont quote me on this, its not something I've ever done myself

His problem isnt emisisons as such, its the ECU not correctly following the lamda signal or the lamba signal being incorrect.

 

[Chip-mk1]

Oh ok, would I see any sign of the CTS failing or is it not something that breaks as such?

unlikely you would see any sign, could also be something as simple as a thermostat not letting it get upto temp enough too.

 

[M@tt_182]

Thanks, I'll feedback to the garage and let them crack on.

 

[_Tom]

Seeing this reminded me I watch something over the weekend where as they tested redex on a Corrado VR6. Before and after it actually gained 5bhp.

Edit. It was Fifth gear.

 

[Maccy]

Seeing this reminded me I watch something over the weekend where as they tested redex on a Corrado VR6. Before and after it actually gained 5bhp.

Edit. It was Fifth gear.

I saw this, I'll take that with a very large pinch of salt...
Then again, I think it's supposed to have better results with older engines.

 

[_Tom]

I saw this, I'll take that with a very large pinch of salt...
Then again, I think it's supposed to have better results with older engines.

To be fair they did say it will probably work with an older engine. But some 182's have racked up the miles now.

 

[M@tt_182]

Still failing! It either fails on lambda or C02 but not both. I'm feeling like it could be time for a special MOT....

 

[Gally]

You need to become friends with an mot tester mate. The Frp left the factory failing emissions testing even red hot...

I did here someone suggest using the probe on another car but that would be madness....

 

[Dan519]

what exhaust. if it's aftermarket, it will make a big difference which tailpipe they put the probe in depending on the design

 

[M@tt_182]

It's a Yozza and they've already done the blocking up trick with no success

 

[Stu172cup]

You need to become friends with an mot tester mate. The Frp left the factory failing emissions testing even red hot...

I did here someone suggest using the probe on another car but that would be madness....

Sometimes my MOT Tester absent mindedly connects it to the wrong car..................................................

 

[Fred@BTM]

It's a Yozza and they've already done the blocking up trick with no success

blocking it up makes it worse!

 

[Dan519]

blocking it up makes it worse!

not if it's sucking air in and making the result look lean, it can look like a leak, thats the main failure on cars with big exhausts. wet rag up one pipe and you've got a real reading

 

[Fred@BTM]

it can throw the emissions light on on ours and cause it to misfire! If its the old style yozza it doesn't matter