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Discussion Starter · #1 ·
sitting in mot waiting room at the moment, I haven't been this nervous since I took my final year exams! its even more stupid because I know it will fail on the sills and tyres anyway
 

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Discussion Starter · #3 ·
probably yes garath I just wanted to see if there was anything else first. just failed on emissions...
 

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Discussion Starter · #4 ·
and I think the electric window just got stuck down...
 

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Daddys little soldier!
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I was always like an expectant Mother when my Mk1 went in for it's MOT. Not that Iever thought she might fail. It is just the thought of someone else deciding the fate of my car. I never used to wait in the test centre though. It would have been like torture.

Lets see what I'm like when my Mk2 goes in much later this year.

Hopefully it won't be too bad.
 

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I've just passed mine this morning
but I spend all afternoon yesterday checking everything bulbs, brake pads.....to find that the right caliper was seize, well the handbrake part.... I finally got it working but the pad is crumbling now. This is due to a stone stuck between the disk and the metallic air part next to it, it overheat as a result handbrake mechanism stuck and pad dead.

But this morning I left with the green paper clear for another year
 

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The verdict is in! It was like torture watching them, everytime they spent longer than I thought necessary on a certain area of the car I felt like shouting at them to move on.

It was way better than I could have hoped for. It didn't fail on the tyres being too worn (advisory) or the holes in the sill (advisory, not within x distance of seatbelt mount so no fail). The sticky caliper didn't show its ugly face and they only did a driving brake test (not on the rollers) so it passed on brakes. It didn't fail on anything else that I didn't know about which is good.

It only failed on the emissions. Any ideas? They tried for ages to get the cat hot enough so it would pass. At one point it almost did, CO was within the allowed amount but then it started rising suddenly again
Guy reckoned it must be running really rich?

 

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Discussion Starter · #12 ·
they had an info board in there which stated the 0.3% CO figure for cars which there was not an exact match (i.e. I assumed an import would come under this category) and that appears to be how they have tested it? Unfortunately for me, it needs the cat test as it is a '96
 

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I just heard my 5 failed its MOT this morning too.


Frustratingly one of the things I failed on was 1.2 lambda on high idle, yet the CO and hydrocarbons were within spec, so in a way it shouldn't matter if I'm running lean. Ah well, better change my AFR target tables and go for a quick tune!

I also failed on handbrake, 95% on one side and 16% on the other, damn. Hopefully it'll just need a bit of adjustment. Got a re-test booked for tomorrow afternoon and tomorrow off work, so better get out and fix things!

Andy, it cant be running that rich if the lambda is 0.98!
 

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Discussion Starter · #14 ·
I just heard my 5 failed its MOT this morning too.


Frustratingly one of the things I failed on was 1.2 lambda on high idle, yet the CO and hydrocarbons were within spec, so in a way it shouldn't matter if I'm running lean. Ah well, better change my AFR target tables and go for a quick tune!

I also failed on handbrake, 95% on one side and 16% on the other, damn. Hopefully it'll just need a bit of adjustment. Got a re-test booked for tomorrow afternoon and tomorrow off work, so better get out and fix things!

Andy, it cant be running that rich if the lambda is 0.98!
sorry to hear about yours, not too bad though I'm sure you can have it fixed in a few hours.
I understand a lot mechanically but this emissions stuff is beyond me. Is there a chance the lambda sensor could be borked or is the fact the reading is acceptable showing that the sensor is ok? Don't know where to start with this
 

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The lambda reading is a reading of how rich or lean the car is, equivalent to air fuel ratio. With 1 (14.7:1 AFR) being 'perfect', less than 1 being rich and greater than 1 being lean. The lower boundary is 0.97, and yours is 0.98, so its ever so slightly rich, but we're talking fractions. e.g. turbo cars run lambda of around .85(12:1 AFR) when in boost.

The reading will have come from the shops lambda probe, so chances are your lambda sensor is fine.

How old is your cat? If its dead then although the air fuel ratio is fine it could be letting the noxious gasses through.

Also worth double checking for leaks in exhaust system, as air could leak/enter the system and distort the lambda readings.
 

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Sorry to hear about emissions woes. Mine stood for a year and just went for MOT and didn't fail on emissions. I did ensure there was fresh fuel and redex additive in the tank first however.
 

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Unfortunately for me, it needs the cat test as it is a '96
Yes, unlucky. As already mentioned, lambda looks OK so probably just needs a new cat to clean up the emissions. Those emissions figures would look reasonably healthy on a de-catted car.
 

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Discussion Starter · #18 ·
So a new cat required then? Anyone got good suggestions of a cheap place to buy one?
 

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