04 Polo 1.2 NCT failure due to high emissions

MataofK

Hi there,
my polo didnt pass NCT and I was wondering is there any point in fixing it; does anybody here have experience with the same problem? I was told by a garage the only way of fixing would be a new engine? Is that so? Im not sure whether to keep my car and pay the price of fixing it or go for a new one; both will cost a lot of money anyway. Apart from the emissions its a good little car and I would like to keep it. Thanks for any help, I appreciate it. Ive attached my NCT form with the test results.

padyjoe

You need a new car, not engine! :-D

I'd start with making sure that air filter, spark plugs working properly, throttle body, map sensor clean, an injector cleaner into the fuel and a blast down on the motorway.

This should sort it unless something else there or you might have noticed something strange happening.

ayux4rj6zql2ph

This post has been deleted.

Leonard Hofstadter

I'm wondering if there is a problem with the catalytic converter? The HC readings are good and healthy, and the lambda is only slightly out of spec. Is there an engine warning light on? What does the fault code say when it's run on a diagnostic machine?

mullingar

Get it diagnosed properly. HC levels are good. When was it last serviced? A blocked air filter will raise the CO levels as the engine can't get enough oxygen. Failing that, I'd wager its the cat.

colm_mcm

And if it’s the cat then you’re looking at what caused it to go.

vandriver

I scrapped an 07 Fabia for the same reason.With rising insurance for older cars,it simply didn't make sense to put any money into it.

MataofK

captainspeed wrote: »

I'm wondering if there is a problem with the catalytic converter? The HC readings are good and healthy, and the lambda is only slightly out of spec. Is there an engine warning light on? What does the fault code say when it's run on a diagnostic machine?

Hi Captain speed, thanks for getting back. Last service was last year in September or October I think I only bought it last June. Garage told me car is burning or drinking too much oil and is smoking like crazy but I never noticed any smoke. It is drinking a lot of oil alright. Shortly after the garage checked it the check engine light came on and when diagnosed it said oxygen level is not right; the garage advised to leave it like that until NCT as fixing would be very expensive. It has been driving fine since. Spark plugs and coil pack got changed last year too and injector checked too, seemingly alright (garage guy had little english). Do you think it's worth it to get it checked properly and what would I be looking at moneywise? The first garage I went to told me basically the car is rubbish and I should get a new car. It's just hard for me to accept as it is driving fine but unfortunately I need NCT too... thanks again for your help!

MataofK

And in case the majority thinks I should scrap it and get a new one, any suggestions for a make and model and year? I know now that polos are known for that emission problem but seemingly other car makes as well. Or any advise what NOT to get. I'm looking for a smallish car, small engine (not over 1.4); not older than 04, just need it 15 mins in the morning to get to work and back in the evening (countryside), don't need it for long distances. Any recommendations? I know the Seat ibizas have volkswagen engines too so I wonder is there more cars i should stay away from if I'd like it to pass NCT. What about ford fiesta or focus for example? Or Toyotas (I heard they are the best for what I'm looking for). Thanks in advance.

Leonard Hofstadter

Driving with a faulty O2 sensor for such a period of time would have a negative impact on the catalytic converter for sure. It can't be burning that much oil because if it was, the HC emissions would be much higher, having said that high oil consumption would increase the CO emissions as well.

If you're looking to buy something else, you really can't go wrong with a Fiesta, Yaris or Mazda 2

mullingar

If that engine is burning a lot of oil over a long time it has killed the cat.

There is no point replacing the cat as it will go again.

That engine needs a complete rebuild and it's well documented that that engine is pure dirt

greasepalm

aye tend to agree bad engines and when run low on oil rings and bore glaze over and oil ring becomes useless and engine burns a lot of oil,easy check is remove spark plugs and look at build up of crap on plugs,so engine and cat gone so not worth it.

lomb

Replace oxygen sensor, air filter and put 1 liter of dipithene in tank. Even if it needs a cat it's 4 bolts and 65 euro. Anyone who is telling you you need a new car over this is crazy. That 04 polo is in reality a 15 grand car if you forget the market. In fact if you had to make it yesterday yourself from scratch to the standard it is I doubt you'd get change from 10million!

mullingar

lomb wrote: »

Replace oxygen sensor, air filter and put 1 liter of dipithene in tank. Even if it needs a cat it's 4 bolts and 65 euro. Anyone who is telling you you need a new car over this is crazy. That 04 polo is in reality a 15 grand car if you forget the market. In fact if you had to make it yesterday yourself from scratch to the standard it is I doubt you'd get change from 10million!

Eh?

It's a 14 year old polo with a fecked engine. It's worthless.

lomb

Ye but there are 'worthless' cars outside multi million quid houses in Ballsbridge including old polos so either they know something or everyone else does. I think they might realise the time value of money.
Getting back to cars, there is nothing wrong in reality with this car the hc emissions are low. Co is created due to an inefficient burn or a defective catalyst. Causes can be many including defective coils plugs mafs air filter oxygen sensor exhaust leak catalyst injectors etc In reality the coils sparks maf oxygen and catalyst are consumables so I would just replace them if they haven't been already. This all assumes the rate of oil use is within reason. My 1.4 golf went through at least 500ml every few thousand miles. This is a normal rate of oil use for these engines probably due to tolerances not being that tight from the factory.
You need someone who has an interest in fixing this who knows what they are doing.

George Dalton

mullingar wrote: »

If that engine is burning a lot of oil over a long time it has killed the cat.

There is no point replacing the cat as it will go again.

That engine needs a complete rebuild and it's well documented that that engine is pure dirt

As above. The cause of your issue is excessive oil consumption, the effect is cat failure and the result is NCT failure.

Don't waste any money on lambda sensors, coilpacks etc.

If you want to take a chance and gamble a few quid on a stop gap fix, get the oil and filter changed, get someone who knows what they are doing to clean the throttle body and reset ECU adaptations, this should get the lambda value back up to 1.00 from 0.98 (which is slightly rich incidentally, not slightly lean as suggested by another poster) which will reduce CO slightly. Then get some decent fuel system cleaner (Cataclean or BG 44K) and try a retest.

But if it was me I'd just sell/scrap the car and buy something else if at all possible.