General Failed MOT

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General Failed MOT

Re: MOT failure - emissions?

Can you post up all the emissions figures as it gives the full story then. As Fiattech says, often a fast run to light off the cat and blow things out works wonders

You can do some basic multimeter checks on your lambda to see if it's readouts are looking right. Always fix any exhaust leaks too of course
 
Re: MOT failure - emissions?

TBH as its just outside the limit i doubt the cat was hot enough - its normally good practice to hold revs at 4000 rpm for at least a minute to purge the system of any residue etc just before carrying out the actual basic emission test.
 
Re: MOT failure - emissions?

Cheers for the replys! Ive got the figures here....

Fast Idle test One

RPM min 2450 max 2950 actual 2752
CO Max 0.300 actual 0.482
HC Max 200 actual 11
Lambda min 0.970 max 1.030 actual 0.990

2nd Fast idle test
RPM actual 2637
CO actual 0.466
HC actual 13
Lambda actual 0.990

everything seems ok with the car, no other issues with driveability... It just seems strange to have that type of problem and feel no effects, thats why I doubt it!

What should I do? Just give it a good thrashing and then ask them to retest before they fit the part?
 
Re: MOT failure - emissions?

Yes, same advice given those figures, a good fast run before the next MOT test will more likely get the cat properly up to temp. Nothing worse than a short trip to the testing station and the thing cooling off whilst waiting

Personally I'd check out the actual O2 sensor readouts (rather than the lambda readings you have) just to make sure the things are reacting properly but that's just me
 
Re: MOT failure - emissions?

As a mechanic myself ive found with experience that a good oil change, plugs, fuel and air filter normally cures it and brings the emmisions down
 
Re: MOT failure - emissions?

hello ,
i just had my car done on my MOT today ,is the same thing
they had change engine oil , lamda sensor , spark plug , however my car emission still failed
the reading

Fast idle
CO 0.68 %
HC 67
Lambda 0.99

second fast idle
CO 0.46 %
HC 50
kambda 1.001

I was told the final option is to change the Catalytic Converter which cost around 300 pounds

Any idea ?
 
Re: MOT failure - emissions?

Is this a Stilo? Which engine?

CO is a over high so it's running too rich. Which lambda sensor was replaced?

Is the engine getting up to the normal temperatures like it should? Or a problem with the engine temp sensor will make it think it is still warming up and needs more fuel
 
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Re: MOT failure - emissions?

Well guess what? It passed today :) obviously, the first tester couldnt be bothered warming it up properly, I took it for a run before they re-tested it, and it passed this time :) thanks for the help! Fiattech, il see you at Stanford :)
 
Re: MOT failure - emissions?

Good stuff. I wonder just how many cats are changed each year when there's really nothing much wrong with them when a good fast run and clear out gets it functioning again

I fail to see what an oil change, as mentioned above, is going to do with an emissions test but i'm always open to offers of sound reasoning
 
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Re: MOT failure - emissions?

Good stuff. I wonder just how many cats are changed each year when there's really nothing much wrong with them when a good fast run and clear out gets it functioning again

:yeahthat:

Can remember my dad taking his 1.8 Escort Estate SI for a thrash down the M62 onto the M18 and back the only problem was is the back box decided to part company as he rammed it down the gears on the approach to a roundabout on an off slip he then had to limp home :bang:
 
Re: MOT failure - emissions?

Hi,

My car (2002 1.6 dynamic) failed on it's emissions twice, both times on the CO being too high. The first time I was told to change the pre cat lambda sensor, which i did. This hasn't made a difference at all.

Strangely, the CO's fine on natural idle :confused:

The car's been serviced at the right intervals all its life, the last one was done about 300 miles ago.

The last figures are:

CO - 0.62% limit 0.30
HC - 28ppm limit 200
Lambda - 0.993
Natural Idle CO - 0.36% limit 0.50%

I'm being told to replace the cat, but I'm not sure about this given the low HC figures and the pass on natural idle. I've had a problem with the fusebox next to the battery getting wet, don't know of this will have any effect on the engine management system or not.

I'm at loss now and I really don't want to spend money on a cat if it's not neccesary, so any ideas will be much appreciated.
 
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Re: MOT failure - emissions?

From my experiences, the 1.6 needs some serious heating up before it can pass the emissions test, seems to get worse as they get older. Has the tester heated the car up properly?? If not, id ask to take the car for a run, get it red hot and while your there get them to test it while its still piping hot. Solved my problem :)
 
Re: MOT failure - emissions?

It's quite easy to check out a Lambda sensor electrically and it's well worth doing that before replacing it

I agree that many CO emissions failures are because the cat hasn't had chance to warm up properly. You don't have to go mad and rev it to death but it's a good idea to book your MOT for a set time so you dont have to hang around and drive in lower gears than normal to the MOT station so the cat is nicely toasting when you get there
 
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MOT fail

fiat stilo 1.6 5 door failed yesterdays mot on blowing exhaust and incomplete suspension coil spring. could anybody give me an idea how much for suspension spring coil, flexy and back box or system post cat please.


anything in wigan area would be most helpful
 
Re: MOT fail

not gona be the cheapest for all that sir , replacing one of my coil springs was qouted 130 inc labour ( so i went for lowering springs all round in the end ) , i had a fail couple of years back , for the quickest i got the mot place to replace it for £105 , as for back box not had to price that yet , but i would reckon in region of £100+
 
Re: MOT fail

My 1.8 just got through the MOT,it needed a front spring,2 tyres,mid exhaust and rear discs and pads,including a service the lot came to £480!!!,the price of a service and MOT was £129-so I supose the £300 for the rest wasn't tooooo bad:eek:
 
Re: MOT fail

fiat stilo 1.6 5 door failed yesterdays mot on blowing exhaust and incomplete suspension coil spring. could anybody give me an idea how much for suspension spring coil, flexy and back box or system post cat please.


anything in wigan area would be most helpful

on my 1.6 I had all discs and pads changed for £190 complete exhaust and 2 front springs for £300 thought its a fair price.
 
Re: MOT fail

do the 1.4 springs fit the 1.6 (im sure they do)

if so i have my standard suspension in the garage..
shocks and springs (all perfect) and only covered 15,000miles.

there up for sale if you want them..
saves you paying £120 for 1 spring.
pm me if your interested :)
 
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