vw polo 1.2 2003 - high co emissions

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Sun 23 Feb 2014 18:38
vw polo 1.2 2003 - high co emissions - stevethesparks

Hi

my son has a polo 1.2 which has covered just over 69000 miles.It was purchased in May for him to learn to drive in and has only coverd 1274 miles since then.

the mot was due so the car was tested and failed the emission test.the mechanic said that the computer showed a possible faulty lambda sensor which he replaced but this has only made the car ok in fast idle test not normal idle.

I have read that a faulty PCV valve can cause problems and would like to know the location of this on the car.I have found what I think is the vavle but need to be sure.Also a pipe that runs to this has also been replaced due to it leaking and I noticed that when started the small flexible rubber piece of this pipe gets sucked in or collapsed.I have read that this is a sign of a faulty valve.

Could any one give me any info on this please,as the mechanic is at a loss too even though i did mention the valve to him,not sure that he noticed it at the time

Thanks

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Sun 23 Feb 2014 19:51
vw polo 1.2 2003 - high co emissions - elekie&a/c doctor

I would guess this is a 3 cylinder engine.Can you post the 3 letter engine code ?(eg Bmd)found on the timing chain end of the engine,or on the sticker in the spare wheel well.Also the actual emissions readings would be helpful.

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Mon 24 Feb 2014 19:50
vw polo 1.2 2003 - high co emissions - stevethesparks

yes its a 3 cylinder engine,i think it is the 6 valve version

the car is at vw at the moment they think it is the throttle body which they are going to clean out and reprogramme the software in the ECU.

I pointed out the collapsed hose on what I think is the PCV valve but it was late and i have not had an answer yet.

they are doing the job tomorrow so i am hoping this cures it,although they did say it could be a problem with the cat though.Not sure that i believe them on that point as its only covered 1274 miles since the last MOT.Could the cat strart to break down if just left standing around?

Can get the engine code tomorrow

first fast idle test CO was at 0.32%

second fast idle test CO was at 0.97%

natural idle test CO was 1.58%

hope this info helps

thanks

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Thu 7 Mar 2019 16:30
vw polo 1.2 2003 - high co emissions - WilliamdlR

Hi
I know this was a while ago now but do you remember what cured your fault. My daughter's identical Polo has the exact same fault.
Many thanks
Will

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Fri 8 Mar 2019 09:30
vw polo 1.2 2003 - high co emissions - John F

High CO is a result of incomplete combustion of a too rich mixture. Here is a link which might help...

www.smogtips.com/failed-high-carbon-monoxide-co.cfm

...the simplest thing I would try first would be to clean or replace the air filter, clean and check the spark plug gap (or replace if done more than 50,000 miles), and then take for an Italian tune up.

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