Board logo

MOT and emissions
dave107 - 24/8/21 at 06:08 PM

Help please

2003 5PW R1 engine and power commander fitted into my car. I believe this engine isnít equipped with a lambda sensor?

Below is what my garage has told me.

Car had itís first MOT today and failed on exhaust emissions of Co% 5.02 it needs to be 0.02 for a car cat equipped vehicle emissions pass. Hydrocarbons burnt fuel content in emissions need to be under 200 ppm. Lambda emissions need to be 1.03 fuel to air ratio or under.
Can the power commander support a map solely for MOT emissions use, whilst also supporting an additional map for daily non MOT use?

Any help will be really appreciated.

obfripper - 24/8/21 at 06:18 PM

Is your vehicle on a new, age related or q plate?
Is there an emissions limit on the v5c?
Do you have a copy of the mac certificate with the vehicle type code?

Depending on the answers for above, you may need either an emissions test as has been carried out, a non cat test, or no test at all.
The mot system does not provide enough information to work this out without 1 or more of the above details, at present it appears to have been tested as a new vehicle with a catalyst required engine which may not be correct.


adithorp - 24/8/21 at 06:31 PM

What reg' do you have. If it's a Q it should be visible smoke only. If age related or new then as it was at IVA and details on v5.

Depends which power commander you have. For PC3 you'd need to load/swap maps then swap back after. With PC5 you can have 2 maps loaded and switch between them. Leaning out you want to get around 0.3% CO and then you'll need a cat to achieve pass levels while not bumping up HC and lambda levels... even then you'll be lucky if it holds steady through the test as it's not closed loop control (even with pc5 autotune that has a lambda) while trying to maintain a steady rpm between 2500/3000rpm.

PS. The HC reading is unburnt fuel, not burnt 😉 and the lambda has to be between 0.97 and 1.03

dave107 - 24/8/21 at 06:45 PM

Hi Dave
Yes car is on a 63 plate, I havenít got the v5c with me now but I believe it stated 0.1 but I canít swear by that. Mac certificate ? Donít know what that is.


dave107 - 24/8/21 at 06:55 PM

Hi adithorp
Power commander 3. Where can I find the maps please are they downloadable from Dynojet?


obfripper - 24/8/21 at 07:34 PM

The mac is the iva pass certificate, the type code has the emissions standard applied at test as the last character.

Does sound like a large chance you'll need to pass a cat test unless the v5 is wrong.

Not the ideal situation, but should be doable with a decent quality cat close to the collector and possibly some mapping on the emissions areas of the fuel and spark maps.

Any idea what may have changed since iva as it must have passed at that point? 5% CO indicates around 12.5:1 fueling, which is fine for full throttle, but not much good for idling conditions or making a catalyst work correctly, you're aiming for 14.7:1 during the emissions test to keep the catalyst hot and functioning.


dave107 - 24/8/21 at 07:45 PM

Dave what Iíll do is go and see the garage first thing in the morning. He has all my documents, we can go through them and check the details, and with the info you guys have helped with it probably will give him some ideas.

Thanks a lot

adithorp - 24/8/21 at 08:08 PM

Originally posted by dave107
Hi adithorp
Power commander 3. Where can I find the maps please are they downloadable from Dynojet?


There are maps on the PC site but they won't do what you need. They'll all be generic for the bike and various known silencers... and for power.
You'll have to have it mapped for your cars set up and to the Mot limits. That needs access to a 4gas analyser and a fair bit of tinkering.

CosKev3 - 25/8/21 at 06:14 AM

5.02 Co is a very rich mixture at idle, you need to be careful with a bike engine as you can bore wash them easily which then means a rebuild.

[Edited on 25/8/21 by CosKev3]