Technical emissions fail after new lambda sensor and new cat

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Technical emissions fail after new lambda sensor and new cat

pk1uk

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hi,i have an x reg bravo sx 1.2 16v,it failed the mot for exhaust emissions.
i replaced spark plugs,air filter,lambda sensor and cat and took it for a re-test.it again failed on emissions.i have attatched the fail sheet.
could anyone help me in the right direction as to why it failed and what to do next?thanks

img034.jpg
 
any help please?

How many miles on the car and when did it last have an oil & filter change? All engines burn a little oil, older ones burn more, and old oil will push up Co2 levels. Try the temperature sensor maybe? If that has failed it could be over-fuelling thinking the engine is still cold.
 
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hi,thanks for the reply,the car has 106k on the clock and had an oil and filter with the mot.
you mentioned the temp sensor and i now wonder if this is a problem i have created.
i bought a performance chip a bout 6 months ago from ebay,it was only a few quid so i thought i'd give it a go as it said it would not harm the engine.
this is the advert for it -
INCREASE YOUR CARS TORQUE & BHP

REDUCE 0-60MPH TIME

IMPROVE RESPONSE AND FUEL ECONOMY

FULLY STREET LEGAL

CREATED TO INCREASE YOUR CARS HORSEPOWER AND TORQUE.

THIS WILL LEAD TO YOUR ENGINE PERFORMING BETTER THEN EVER!!!

You will get complete simple step by step instructions for easy install, it's really easy to fit.

No special skills are required.

Will fit all engine sizes and types for made after 1988, providing they are fuel injected and not turbo or not diesel.

The mod itself is a small resistor that tells your engine control unit (ECU) that all of the air coming into the engine is cold and therefore dense and packed with oxygen. The ECU then takes this information and tells the injectors to fuel slightly more. This in turn makes for a more powerful detonation in the cylinders and releases the full potential of your engine.

The mod will allow your engine to release its full potential, your power curve will be smoother with flat spots ironed out, your 0-60 will be quicker so you can get off the line faster and your car will experience an increase in top end speed. Also in some cases depending on how you drive, it will boost your MPG by 5%.

The Mod chip will allow you to boost the power of your cars engine.

Nothing else will be effected giving the car a 100% benefit.

Provides 20 BHP+ more to the vehicle.


i only used the chip for a few months as it didnt make much difference so i removed it and reconnected the sensor

could i have damaged the car by using this,thanks.
 
:( OK. Well... my car is re-mapped, because the chipping thing didnt look right to me, especially a cheap chip, all it does (if it is a chip and not a resistor) is over-fuel the motor by fooling it electronically. It might pass the MoT with the chip removed or the over-fuelling may have caused bore - wash, where oil is washed from the cylinder bores by high levels of fuel, leading to high oil burning.

Can you post a pic of the "chip"? If it were my car that is exactly where I would start looking for the overfuelling and high Co2 levels. Now you have removed it,(was that just before MoT?) the ECU may have to re-learn your driving style.
 
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thanks for the reply,although bore - wash is something i know nothing about and wouldnt know where to start but i do alot of work myself cos i'll give anything a go
here is a pic of the "chip" it (was a cheapie from ebay)
detail
http://profile.imageshack.us/user/pkoneuk/images/detail/#23/photo0114aqx.jpg

and yes it was removed just before the mot
what should i look at/replace first,i appreciate your input,thaks
 
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thanks for the reply,although bore - wash is something i know nothing about and wouldnt know where to start but i do alot of work myself cos i'll give anything a go
here is a pic of the "chip" it (was a cheapie from ebay)
detail
http://profile.imageshack.us/user/pkoneuk/images/detail/#23/photo0114aqx.jpg

and yes it was removed just before the mot
what should i look at/replace first,i appreciate your input,thaks

Yea you got the resistor con there fella... cost about 5p from an electronics shop they do... :eek: Anyhow, try disconnecting you car battery overnight, that should make the ECU forget what the resistor told it to do, then the ECU will have to re-learn what it needs to know for a few miles, although how you go about that with no MoT I'm not sure.... Try the Search function using the keywords "chip" and "resistor" see what advice pops up there?

Heres a link to another Thread I started on this :-
https://www.fiatforum.com/leisure-lounge/196448-now-being-advertised-ff-via-e-bay-0-a.html

And a longer Fiat Forum discussion on the bloody things and selling or buying them. https://www.fiatforum.com/leisure-lounge/43711-just-bidded-some-reason-seems-cheap-lol-2.html
 
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well, are u usre that (air temp)sensor is reconnected correctly?
 
Yea you got the resistor con there fella... cost about 5p from an electronics shop they do... :eek: Anyhow, try disconnecting you car battery overnight, that should make the ECU forget what the resistor told it to do, then the ECU will have to re-learn what it needs to know for a few miles, although how you go about that with no MoT I'm not sure.... Try the Search function using the keywords "chip" and "resistor" see what advice pops up there?

Listen to what Ffoxy is telling you, :)
Get the chip and put it in the bin. It tricks the car into running cold start.

putting more fuel in is only good on a cold engine that is not running efficiently as it will try to stall. Once the engine is warm more air can be added.

The resistor tricks the car into thinking its always cold and as a result puts too much petrol in. The car thinking its in cold run mode wont try to correct the amount of air which is required for performance.
instead it will run rich reducing mpg, and all the excess petrol wont always be burned it will flood the bores of the engine.
 
thanks for all the advice,i will disconnect the battery overnight,as for driving im really not sure,would i have to give it a good blast through all the gears or just up and down the street?and for how long?with no mot im in a catch 22.
thanks again
 
thanks for all the advice,i will disconnect the battery overnight,as for driving im really not sure,would i have to give it a good blast through all the gears or just up and down the street?and for how long?with no mot im in a catch 22.
thanks again

I agree.... you might get away with running it with the front wheels suspended but that will change the torque characteristics, plus you wont know if anything has changed until you go to the Test Station again.

Yours is a perfect example of what those crap*y resistors can do to a car so Post up a warning Thread on it from your own personal experience I say.

Hope you get it sorted dude...
 
well i shuld recomend u to run car at idle for lets say 10 min then when warm, some higer revs at ~70 mph speed or so, as what is normal, just at 1 spot revving wouldnt do so much good...
 
well i shuld recomend u to run car at idle for lets say 10 min then when warm, some higer revs at ~70 mph speed or so, as what is normal, just at 1 spot revving wouldnt do so much good...

No MOT and he isnt gonna break the law now is he?
 
looks to me by the emmistion read out the lambda is high are you sure you havent got a small leak in the exhaust system which would effect the lambda reading (y)
 
Modern engines are capable of being well inside the emission requirements, so something is well out. Giving the car a good run is not really needed to get it back into order, the ecu can work that out if it gets the right info. Faulty MAP and air temp are the most obvious, look for any leak in MAP pipe etc and replace MAP if needed also air temp sensor.
On the 8 valve models cambelt timing causes low vacuum with resultant MAP out of range.
T.
 
well after disconnecting the battery i took the car to a quiet road,put some more treatment in that i had kindly given to me and thrashed the life out of it.i also found a small leak in the exhaust where i needed a new clamp for where the cat is connected.dont know which of these it was(possibly both)but it passed the emissions.thank you eveyone for your replies and input,especially Ffoxy,you were of great help,cheers
 
well after disconnecting the battery i took the car to a quiet road,put some more treatment in that i had kindly given to me and thrashed the life out of it.i also found a small leak in the exhaust where i needed a new clamp for where the cat is connected.dont know which of these it was(possibly both)but it passed the emissions.thank you eveyone for your replies and input,especially Ffoxy,you were of great help,cheers

:) It was nothing pk1uk... happy to help, I get enough help here myself, its good to give some help back (y)
 
Were would this resistor be if fitted?? Any pics??

My 1.6 16v Brava has had CO emmision fail since i bought her, currently failed MOT again. Just want to check make sure the B****Y bit isn't on mine.

Cheers.
 
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