MOT fail due to CO non lexus

[jackcramerr]

Not Lexus car.

Mot failed due to high CO. Car consumes engine oil but no smoke. 

Is it time to bin the car or can I go to other center than kwikfit and re try? 

Do redex and stuff work? Car wasn't being used for well over a month and driven straight for MOT. Any suggestions? Thanks.

 

[NemesisUK]

You could try an "Italian tune-up" immediately prior to the retest

[peachy]

Put a bottle of redex in the tank and give it a good belting on the motorway for 20 mins before the test. It could well get it through jack 😉

 

[Vintagesixtysix]

Diesel or petrol?

If a good blast & additive don't work.

There is a terraclean thread going at the moment......most folks want to see/feel huge performance gains which are rarely available......but can really help with bringing down emissions towards acceptable if too high. They can measure the start and finish levels so it is tangible. £70-100.

Might get you through?

Sent from my iPad using Lexus OC

[peachy]

I had a vauxhall astra 2.2 Sri a few years back which failed the mot due to emissions.  The garage adviced me to put in a bottle of fuel cleaner and give it a good belting before the re test which I did and the car passed.

[jackcramerr]

It is a 2.0 petrol. I will put redex in tomorrow. 140k miles on clock.

Won't police stop me for no mot?

 

 

[jackcramerr]

To add, it failed CO at idle by 1 point. All other readings are well in range.

[ahmedali44]

Forte petrol additive is better as always use forte diesel in my taxi with 410k on clock pass emissions every time. It's bit more expensive then redex but works better too 

[madasahatter]

Cataclean works briliantly.

[jackcramerr]

Can I drive the car around for italian tune when mot re test is on the same day? 

[johnatg]

Not legally, but you have a good chance of getting away with it if you have a retest booked.

[Verbout]

10 hours ago, jackcramerr said:

Can I drive the car around for italian tune when mot re test is on the same day? 

You can drive the car TO a pre-booked appointment only.

The route you take is open to interpretation. :)

[Texas]

Chances of getting pulled over for no Mot are pretty slim, no insurance that's another ball game! You don't actually have to go speeding to 'Italian tune' your car and risk getting a speeding ticket ( via any speed cameras) . Just hang onto each gear a little longer than normal (if it's a manual that is) as it's the revs of the engine that's gonna do the work inside the engine not the actual forward speed in MPH if that makes sense.

paul m.

[madasahatter]

3 minutes ago, Texas said:

Chances of getting pulled over for no Mot are pretty slim, no insurance that's another ball game! You don't actually have to go speeding to 'Italian tune' your car and risk getting a speeding ticket ( via any speed cameras) . Just hang onto each gear a little longer than normal (if it's a manual that is) as it's the revs of the engine that's gonna do the work inside the engine not the actual forward speed in MPH if that makes sense.

paul m.

What you say is true, i have been told its 3rd and 4th gear that need the revs. And also hold onto them for a while,do not change up to quickly.

[johnatg]

I wouldn't worry too much about specific gears - it can be a bit hard to reach high revs even in 3rd in London (although maybe in Jack's version of London it may not be too bad! ) - proper high revs in 3rd even is probably over 80 - many cars will do 60 in 2nd. Hold 2nd for reasonably long periods if it's not a dual carriageway/motorway. You want to be at 4500-5500rpm for a while.

[jackcramerr]

Ok it passed mot.

I am not understanding the results. I am compaing the first fail test result with second pass resukt.... the limits are different.... One says CO should be less than 5. The other ( passing result) says less then 3. And it passed just at 2.xx so at a margin.

What is the usual CO level? And how can I reduce it further?

[johnatg]

It depends on the age of the vehicle - what year of first reg is it and what are the results? We could give more direct answers if you weren't so coy, jack!

[Texas]

20 minutes ago, johnatg said:

It depends on the age of the vehicle - what year of first reg is it and what are the results? We could give more direct answers if you weren't so coy, Jack!

I reckon he plays poker!😀😀😀

some causes of high CO http://www.smogtips.com/failed-high-carbon-monoxide-CO.cfm

 

paul m

[jackcramerr]

its 2006 reg but car is 2005. 2.0 petrol.

[jackcramerr]

I'll need to check mot sheets again for the units. I googled thanks to John's tip and came across dft website.

0.580  CO Emissions
[g/km or mg/km under Euro 5/6]

 

And I am sure the second pass test performed said pass results of .29xx and limit of <.3 to pass. So it is on the border. 

The first test that was a fail had limit of <.5xx and it failed as it was .5xx

I will check the sheets and provide exact info

[Farqui]

The emissions test can be tried a number of times (5?) and the reading usually improves/drops each time. Hopefully it's then low enough to pass before the last allowed attempt, to gain a pass.

[jackcramerr]

Ok first test was performed a week back. Result was Fail, then Pass then Fail. Limit <.5 and failed as it was .5xx

Second test was performed yesterday only once. Pass. Limit <.3. And it passed on .29x

 

 

[johnatg]

The correct limit is 0.3% CO at natural idle speed. That applies to cars first reg from 1/9/02. The 0.5% limit is for cars reg from 1/8/95 to 31/8/02.

The other limits applying to your car are (at fast idle - between 2500 and 3000 rpm)) 0.2% CO, 0.02% Hydrocarbons and lambda 1 +/- 0.03 (lambda is the value derived from the Oxygen sensor).

All measurements by volume.

That comes from 'In service exhaust emission standards for road vehicles - Eighteenth edition' published by DVSA  (222 pages of light bedtime reading!)

NB - the actual readings obtained from a car in tip top condition should be much lower.

It sounds as though the car could do with a dosage of Cataclean - excellent stuff. If that doesn't work for next time you might be in for one or both of oxygen sensor/catalyst.

[jackcramerr]

Thanks John.

I used Redex and Tesco Premium petrol to get to a pass. With Italian tune.

Should I still pour in Cataclean now or wait for next mot? Or just sell the car off? I wouldn't be able to tell if Cataclean worked... will I?

[johnatg]

Maybe wait until next time - but do it a month or so before the test at least and put the Cataclean in a half full tank and run it near to empty. Try and do some spirited driving on the way. And use the car more regularly - or sell it!

Redex and similar fuel cleaners are more for cleaning the fuel system and injectors (which certainly can help emissions) - Cataclean is more specifically for cleaning the oxygen sensor and cat. But it can't restore totally shot stuff.