Stiglet

Active Member
Feb 12, 2010
889
3
Surrey
Thought I'd post this here aswell coz I do drive a mark 4 and hoping for some help.

I have mark 4 Ibiza 1.4 sport. Last 3 months engine management light has come on 3 times. And has just come on again !! I've had new plugs, 4 new coil packs and a bank 1 lambda sensor replaced plus all codes cleared . What's next ? Got a nasty feeling its the cat next? Any ideas please please please.. Starting to get fed up and skint lol.

Thanks
 
What code are you getting?

Could be the downstream lambda, after the cat. Unless you have good reason to suspect the cat might be knackered, that is.

If it turns out to be the sensor, then it isn't urgent as it's really just there to nag you about a potentially broken cat.

Mine triggers a light now and again, even though the cat has been fully replaced. I am resetting/ignoring it until I feel particularly flush.
 
Don't have a code yet , taking it to my garage on Monday then may take it to a place that can check cats. Not the RSPCA lol. At least engines running fine but just dam annoying before Xmas .
 
What makes you think that it is/could be the cat, changing the coils and plugs and first lambda - was that prompted by the engine management light coming on and if so where the fault codes logged credible and connected with the parts replaced?

There are quite a few things that can bring that light on, but I thought the emissions light would have come on if the post cat sensor was reading high levels for some reason.

One issue could be the EGR valve, now if it is the EGR valve flow, then I'd reckon that it will be due to gunging up of the end of that, or rather its port on the throttle body, only action needed there is a quick clean up of the throttle body or its interface plate if there is one.

Are you seeing the engine management light coming on, staying on for a few days then going off, only to come on again some time later etc etc ? If so then you probably have an intermittent fault.
 
Light came on when 2 coil packs went one after another . Then came on reporting bank 1 lambda sensor but I forget the code ? 4020 maybe ? Haven't had it read after the latest light yet. Will get it done Monday .
 
4020 is usually caused by post-cat lambda complaining about poor emissions.

How old is the cat/exhaust and what kind of nick is it in?
 
Exhaust since new in 2005 so it's 8 years old. Seems ok but not looked underneath ? Cars only done 36000 miles since new. Only do about 5000 miles a year roughly. Was thinking of taking it to a exhaust place that tests cats.? Or get fault code first?
 
If you want to, you could buy a cheap but good, VAG scan tool, ie fault code reader - and "clearer", Gendan for instance sell one for about £30, no intense skill required to use it - just plug in to diagnostics port ask it to read engine codes, write down numbers of codes logged, clear codes, shuffle off and stuff the codes written into your old friend Google as "VAG fault code *******" and you should get some answers, not a cure, but useful info for handing to whoever is fixing it and it lets you see is there is a pattern, ie credible codes being logged and if they seem to be urgent of not.

I've just looked at www.gendan.co.uk and the tool is £26.95 which I think is the price to get it delivered to your door.

I've got one of them and it lived in the boot of my Passat B5, now it lives in the boot of wife's Polo 9N as my current car is too new for it!!

For it is worth, the exhaust on my wife's late 2002 Polo 9N 1.4 16V 75PS BBY, is still the original one (outer skin on back box is split but kept shut with large Jubilee clip - also front flexi has been replaced), and the mileage over 98K it is only ever fuelled with premium brand fuels and currently Shell 97 octane stuff while it had a pinking issue which could have been "oil drinking" related.

Seeing as I've mentioned "front flexi" being replaced, your front flexi is not leaking at all?
 
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If you want to, you could buy a cheap but good, VAG scan tool, ie fault code reader - and "clearer", Gendan for instance sell one for about £30, no intense skill required to use it - just plug in to diagnostics port ask it to read engine codes, write down numbers of codes logged, clear codes, shuffle off and stuff the codes written into your old friend Google as "VAG fault code *******" and you should get some answers, not a cure, but useful info for handing to whoever is fixing it and it lets you see is there is a pattern, ie credible codes being logged and if they seem to be urgent of not.

I've just looked at www.gendan.co.uk and the tool is £26.95 which I think is the price to get it delivered to your door.

I've got one of them and it lived in the boot of my Passat B5, now it lives in the boot of wife's Polo 9N as my current car is too new for it!!

For it is worth, the exhaust on my wife's late 2002 Polo 9N 1.4 16V 75PS BBY, is still the original one (outer skin on back box is split but kept shut with large Jubilee clip - also front flexi has been replaced), and the mileage over 98K it is only ever fuelled with premium brand fuels and currently Shell 97 octane stuff while it had a pinking issue which could have been "oil drinking" related.

Seeing as I've mentioned "front flexi" being replaced, your front flexi is not leaking at all?

Thank you so much for your reply . I will certainly check your link out.
 
check the timing
is the engine same as mk4 golf 1.4 with the 2 timing belts
 
latest update. went to my garage this morning and they plugged it in and got code 4020 again!!! upon research it can be either lambda sensor or the cat. having had the first one replaced he checked my emmissions( cant spell it lol) and the cat was working fine so we have replaced the post cat sensor and cleared all codes. now will have to see how this goes ....watch this space. fingers crossed that's it!! and thanks for all your help.
 
Well, the fact that the cat seems to working fine is good news, hopefully replacing the S2 sensor has sorted this out.

At least now your cat has a good protection as you can give it by replacing some coils and plugs - and pre-car lambda sensor.
 
Well, the fact that the cat seems to working fine is good news, hopefully replacing the S2 sensor has sorted this out.

At least now your cat has a good protection as you can give it by replacing some coils and plugs - and pre-car lambda sensor.

Apart from wrapping the cat in cotton wool not much more I can do lol. Garage was very good to do the sensor there and then . Does help having parts store opposite .
 
Haven't got bill for 2nd sensor . That was 70 + vat. First sensor was 113 + vat total .170 quid total including labor.