Emissions MOT failure clues anyone ?

[SilverVti]

Hello

I wonder if anyone can help. My S reg VTi has just failed it’s MOT for the first time in 10 years. It failed on 1 point emissions. I suspect the reason is because of a combination of things

1) It was first thing in the morning and the engine/cat had not fully warmed up

2) The engine management may be a bit out of sorts as I ran out of fuel a week ago and it’s currently running a bit lumpy

3) The test station are trying to sell me a new cat for £120

I’ve had a look through the forum and have got some inspiration from this post

viewtopic.php?f=62&t=46 that talks about resetting the ECU

and this one viewtopic.php?f=14&t=3210 where Rich and Paul made some suggestions.

The test was run 1st thing in the morning and the car was cold. The garage ran the tests twice – first time they hadn’t got the printer turned on and it failed. They then took it round the block to try and re-tested it. These are the 2nd set of results.

Fast idle test

Engine Speed 2450 – 3050 Result 2587 rpm = Pass

CO Max 0.3% result 0.59% FAIL

HC 21 ppm Pass

Lambda 0.99 Pass

Second fast idle test

Engine Speed 2450 3050 Result 2796 rpm Pass

CO Max 0.3% result 0.33% FAIL

HC 7 ppm Pass

Lambda 0.99 Pass

Natural idle test – passed

Engine speed 650 – 1000 rpm 743 Pass

CO 0.26% Pass

The second set were somewhat better but not enough to pass. The tester spoke to a colleague who said that it was more than likely the cat and quoted £120 for a new one fitted.

These are the options I see at the moment.

Option 1 Add Fuel system cleaner and drive round in the hope that it cleared the lumpiness and/or clogged fuel / cat.

Option 2 Reset the ECU as described here viewtopic.php?f=62&t=46 in the hope that the ECU re-calibrates itself to normal after having a fuel outage.

Option 3 Give it a caning and get it to a friendlier test station for a re-test. (£40 for full test)

Option 4 get a new cat and get it re-tested at the same station for £130 (£120 + £10 re-test)

I have booked a new test with a friendly station tomorrow and have to figure out what to do today.

Any suggestions / clues are most welcome.

Thanks

SilverVti

Ps I’ll work out which MA/MB/MC I have when I’m not under the kosh for an MOT

(I suspect it's an MB6)

[civicturbo79]

you should never do a cat test when its cold . At the end of the day it was 0.03 % out i would have took it out and drove it as hard as i could and put it back on with the cat red hot it would have passed then im sure . If the cat was not working the co2 would have been 2-3 % . Rich.

[SilverVti]

Hi Rich,

Thanks for your comments. I'll see if I can locate the diagnostic plug tomorrow and see if there is anything else going on.

Thanks

Steve

[SilverVti]

Phew, what a joke !

I went to another test station today, and they revved it up to around 5k for 20-30 sec before starting the emmissions test. It then passed with no problem.

I went back to the original garage and demanded to know how they could justify recommending a new catalytic convertor that didn't need replacing. Initially got loads of excuses but stood my ground. After demanding a chat with a manager around the area of "recommending unnecessary work" and "ability of tester to put the car in a favourible condition for the test" they gave me my money back.

Job done. Not going there again. Robbing gits !

[civicturbo79]

Well done mate , just shows what standing your ground can do . Rich.