[AWSAWS]

Hi,
I have my first MOT in June with the JB4 and catless downpipes installed. What is the deal with passing the emissions test?

Would the JB4 be set to off (map 0) or map 4 during testing? I wonder if it's 4 so that it deletes any cats removed warnings with autoclear or 0 so that the tester can read the OBD port?

I gather that once warm the secondary cats are sufficient to keep emissions within the limits. Is that what people have found?

Thanks

[Sparky68]

I've never had a tester plug into the OBD, make sure you arrive just before your allotted MOT time and get the car nice and warm.

[AWSAWS]

Originally Posted by Sparky68

I've never had a tester plug into the OBD, make sure you arrive just before your allotted MOT time and get the car nice and warm.

Thanks Sparky. Did you set JB4 to map 0?

I read the test and it said the tester has to run the car until oil is at operating temp which for a 335i they have listed as 60C even though it seems to be 70C if you look at our oil gauges.
They have to run the car for a while at x revs (like 2500 rpm) for a certain amount of time before the test, measuring hydrocarbons and carbon monoxide.

[Sparky68]

Left it on 3 if I remember correctly

[doughboy]

The JB maps won't have any effect at idle / MOT revs / no boost levels. Best to leave it as normal, as changing it pre-test is more likely to upset the adaptations.

If you turn it to map zero, then the emissions light will come on and you'll fail for that then.

You need a friendly MOT man (not a chain place) that will test it hot, no use leaving in at kwik fit to go cold before they check it. Oil temp is irrelevant to this as the secondary CATs don't get warm on idle, so it tneeds a good thrash before the test, then preferably on the ramps soon after. I told them mine had hi-flow cats in the DPs (when they were really decats) they don't know any better, and the fact the O2 sensors are there still makes them look like CATs, so I said they need to be warm and they were fine with that, just take it for a spin and back on the ramp.

Also, a good thrash, plenty of revs and get it very hot the day before to clear any soot etc from the CAT internals, you want them to be tip top to cover the lack of primary CATs.

Mine failed first up, but after a good thrash the next day it passed easily. It's still way off the factory readings, but the MOT levels are so lax as they've hardly changed in over 20 years.

BTW - OBD port is not used in the MOT test.

[AlanYoro35i]

i drove a good lap around our ring road before getting it done

[zltm089]

Plus one on what Mike said.

Friendly mot guy is the way to go....offer a couple of beers! ;-)

[AWSAWS]

Thank you for the info guys!

[AndyN]

How did you get on with your MOT Sam?

Mine failed today, I only just read this thread.

Pass is 0.2% CO2 and mine was at around 1.2%!

[RajB]

Originally Posted by AndyN

How did you get on with your MOT Sam?

Mine failed today, I only just read this thread.

Pass is 0.2% CO2 and mine was at around 1.2%!

I'm assuming that's because you've gone catless DPs and removed secondary cats with the Remus Race system.

You need a friendly MOT tester as unless you keep at least one set of CATs you won't pass. I had the AR catted DPs with Akra DP back system and it just about passed. Now I've gone catless too no way it's passing straight.

[AndyN]

The Remus quad I have is just the back boxes so the secondary cats should still be in place.

I was getting a few odd codes I hadn't seen before with the Evolve Stage 2 map I had (which I've bloody had enough of, it's been rubbish and thrown way too many random codes).

- Fault: Lambda probe front catalyst 2, adjustment control
- Code: 002C32
- Fault: Lambda probe front catalyst, adjustment control
- Code: 002C31

I have the VRSF DPFIX installed, which is a bad idea according to this thread - http://www.n54tech.com/forums/showthread.php?t=30352

So, plan is to remove the DPFIX, get my JB4 installed at long last, let the adaptations run in, throw in a bottle of Cataclean and make sure the car is as hot as possible before getting it retested!

Not sure if that's the best way forward but from all the info I've found so far it should help matters a bit at least.

Oh, as an aside, just found one of my Ohlins shocks misting oil, trying for a replacement under warranty as it's only 8 months since installation!

[RajB]

Originally Posted by AndyN

The Remus quad I have is just the back boxes so the secondary cats should still be in place.

I was getting a few odd codes I hadn't seen before with the Evolve Stage 2 map I had (which I've bloody had enough of, it's been rubbish and thrown way too many random codes).

- Fault: Lambda probe front catalyst 2, adjustment control
- Code: 002C32
- Fault: Lambda probe front catalyst, adjustment control
- Code: 002C31

I have the VRSF DPFIX installed, which is a bad idea according to this thread - http://www.n54tech.com/forums/showthread.php?t=30352

So, plan is to remove the DPFIX, get my JB4 installed at long last, let the adaptations run in, throw in a bottle of Cataclean and make sure the car is as hot as possible before getting it retested!

Not sure if that's the best way forward but from all the info I've found so far it should help matters a bit at least.

Oh, as an aside, just found one of my Ohlins shocks misting oil, trying for a replacement under warranty as it's only 8 months since installation!

Ah ok interesting then. I would have thought it would have passed unless it just wasn't hot enough. The codes I think more just point to the fact the DP CATs are no longer in place and the DPfix not quite working as it should. Remove that first and fit the JB4 and see how she goes.

Also very interesting on the Ohlins and thats not good tbh. I certainly hope it's a one off as I went Ohlins after all the constant praise on here lol.

[Aragorn30d]

1.2% is way beyond just missing cats.

A healthy car with no cats will return around 0.5%.

Theres definately something wrong with the fuelling on your engine, and the lambda codes are highlighting that too. Could be an air leak, bad maf or a tune issue for instance.

[Dann]

I'd make sure that the car is 100% hot before getting it emissions tested.

My old 328i failed and even with new Lambdas it failed again until I drove it for about 30miles in 4th on the motorway. An italian tune up probably wouldn't hurt either.