NCT failure - emissions too high - cause?

MsGinger

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I have put my 1998 Peugeot 106 through the NCT twice in the last couple of weeks. Before the NCT I took my car to a specialist exhaust centre as I had a new piece of exhaust fitted a few months ago and I felt it was not sealed properly. They told me they sealed it that day (no charge).

At the first NCT the following day, the mechanic told me that the exhaust was not sealed properly, where the old piece met the new piece. There were a also a couple of other minor things. I took the car to another guy, and he fixed all the things on the list and told me that he resealed the exhaust again.

Today I took it for the re-test and it failed again on emissions, it was only marginally lower than the first time (1.061 Vs 1.066). The max for this vehicle is 1.03, so it doesn't seem to be hugely out (that's a very uneducated guess, maybe someone else will correct me).

My question is whether there is any other reason that the emissions would be too high? I'm worried that this is something that's going to cost a lot to repair, and I've already spent almost €500 between servicing it for the NCT & paying for the NCT's. I was hoping to change it next year, and I really don't want to spend much more money on it.

Any advice would be appreciated.

Thanks,
Ginger
 
Its all about the lambda and catalytic converter which is different to the exhaust. Id bring it back to the original place where you got the exhaust changed and ask them did they look at the at converter when changin the exhaust. 500e seems very excessive for me to be changing the exhaust unless you brought it to a high street brand dealer , e.g, renault, mazda. Any of the regular exhaust fit, fast fit, exhaust'r'us crews will fit a new exhaust from the generic exhaust makers, bosal, for 150-160e. Dont want to scare you but I had the same problem when I failed the nct a couple of years ago and it cost me nearly 600e for a new cat converter in a 98 renault to get the lamba emmissions down far enough to pass the nct. There was an audible screech when I was given the bill. I was later told by a friend in the know that 600e sounded about right, most of it was labour so unless you know someone, be prepared!!!
 
Hey MsGinger,
There are many products on the market that you can use to clean the engine and reduce the emissions.I used "Dipothane" but I have a diesel engine, i'm sure any motor factors would help you out with a good one for a petrol car.Not expensive.Just add to the petrol tank when you fill up.
I am asuming there was no reference on the failure sheet that the exhaust was leaking for the second test, and that the only failure you have is emisions.If your getting rid, then theres no point spending cash on the exhaust if you don't have to.
 
Hi MsGinger
I had the same issue with my car, i ended up getting all 3 replaced. you can buy second hand Cat Converters for approx €180. that was the first thing i replaced and still didnt' fix it, i then got a new exhaust - no joy! it ended up being the lamba (€75) that was the problem. you should also get your garage to do an emissions test when they have worked on it before your re-test - saves a lot of time.
 
Thanks all for suggestions, I think I'll try horgak's first - it sounds like the cheapest option! I'll let you know how I get on....
 
Well the problem is the catalytic converter.... was driving merrily along the other day when all of a sudden my little cars started sounding like a lorry! I was quoted 230 to replace, which doesn't seem too bad and hopefully this will be enough to get it through the NCT....
 
hello,my car failed today on emissions the high idel is6.28 vol% the ppm is 767,i have spent 900 already getting ready for nct,i only have the car 8 weeks,i need a bit of help any ideas would be great thanks.
 
smurf37 you aer giving very little information and please capitalise and punctuate when you next post.

ONQ.
 
My brother is a mechanic and he added something to his car on the day of his NCT to reduce emissions and passed no problem - a 1992 car.

Too late to call him now, but I'll ask him tomorrow and post again.
 
Yes...I am very sorry about my grammer.This is the first time i have used this site.My car is a Mitsubishi fto,1.8 petrol.I would be most grateful for any ideas,hints.Thankyou.Rosie
 
Remve the air filter prior to the test and that may help but it does not cure the problem. If it still fails then I would have a look at the lambda sensor,
 
thanks for that krissovo,much appricated.i have ten days before i am back for retest.
 
Asked my brother what he used - sorry if this is a bit vague but he said for a petrol engine go into any motor factors and ask for product to reduce emissions - he said "they'll know what you mean", it costs around €10/12. You add this liquid to the petrol tank just prior to the NCT.

On a diesel car he said there are various options including adding kerosene to the fuel tank.

I can get more specific info off him when he not so busy over the weekend if anyone wants it.
 
It's probably Dipotane as referred to in a post above - add it to your petrol when the tank is about 1/4 to 1/8th full
 
hello,my car failed today on emissions the high idel is6.28 vol% the ppm is 767,i have spent 900 already getting ready for nct,i only have the car 8 weeks,i need a bit of help any ideas would be great thanks.

Why did you buy a car with no NCT and then spend 900 on it?

Your mechanic should be able to test the emissions and tell you why its failing.
 
i took the seller of the car at her word,that the car ready for NCT.I will not make that mistake again.
 
There was a product on the market called 'Redex ' which helps reduce emmissions , and it also helps increase miles per gallon - not sure if it is still available .

A mechanic told me that if the lambda sensor is the cause of emmissions , that it is caused by driving on low fuel in tank/ fuel light on too often.

[broken link removed]
 
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I bought a car recently with no nct trusting the previous owner but it failed twice on emissions after 10days..... later it came out that lambda sensor was connected wrong (ie, +ve to -ve and viceversa)... a garage figured out by putting on computer...
 
Yes...I am very sorry about my grammer.This is the first time i have used this site.My car is a Mitsubishi fto,1.8 petrol.I would be most grateful for any ideas,hints.Thankyou.Rosie

Having read all the contributions you really need to bite the bullet and pay for a mechanic to take a good look at your car.

All the safety items should be checked urgently to make sure you're not driving an unsafe vehicle.

Mitsubishi's are usually clean running and reliable.

Yours is a sports model and pretty tough by all accounts however it could have been thrashed from cold by a stupid driver or allowed to miss a service.

You should also check its not a ringer or welded together wreck - they get crashed and I think the law is still lax in this area.

There are too many inscrupulous people out there only thinking of themselves and you have to watch out for them.

ONQ.
 
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