Mot fail co reading .700

motorguy

new plugs, leads and maybe a coil pack.

All of those affect how well the fuel burns and therefore emissions.

i'd be surprised if new leads and plugs didnt sort it.

321p123

I want to fix/find the source of the problem, not bodge it, that's why I'm asking, I just don't want to pay thousands on something if its not that issue, I used redex as a one off just to help clean an old engine, not as a bodge. 

321p123

These old vauxhalls always have a light on 

321p123

Bank 2 I believe was the fault so post cat lambda and high emissions, so I'd say the cat does look done? 

facade

It passed on lambda, so the mixture is correct, and the pre-cat lambda sensor is fine.

The post-cat lambda sensor only tells you the catalyst isn't doing anything to convert CO to CO2- so that is working too.

As the mechanic and the others are saying, the catalyst isn't working.

You might be able to take it off and clean it with Magic Fluid (fairy liquid and water and hose it out), but tbh on a 1.8 Zafira it will be due to all the oil that the engine burns killing the catalyst.

£130 for an eBay cheapie that will last 2 or 3 years, no point buying anything better if it is an oil burner (surprise me and tell me it doesn't use a drop of oil in 10,000 miles, rather than the more likely 15-20 litres!)

321p123

facade said:

It passed on lambda, so the mixture is correct, and the pre-cat lambda sensor is fine.

The post-cat lambda sensor only tells you the catalyst isn't doing anything to convert CO to CO2- so that is working too.

As the mechanic and the others are saying, the catalyst isn't working.

You might be able to take it off and clean it with Magic Fluid (fairy liquid and water and hose it out), but tbh on a 1.8 Zafira it will be due to all the oil that the engine burns killing the catalyst.

£130 for an eBay cheapie that will last 2 or 3 years, no point buying anything better if it is an oil burner (surprise me and tell me it doesn't use a drop of oil in 10,000 miles, rather than the more likely 15-20 litres!)

It used to have a mild oil leak from gasket, but I changed the cover, it doesn't seem to burn oil... I can get a cheap one off ebay for 190, so will try tomorrow to get the old one off without issues.
Cheers 

Mildly_Miffed

321p123 said:

Mildly_Miffed said:

One of the jobs of the cat is to oxidise CO (Carbon Monoxide) into CO2 (Carbon Dioxide).

So if your CO is high - and it is, pass limit is 0.2%, so 0.7% is 3.5x that - then cat is definitely the first suspect.

What fault code are you clearing? Post-cat lambda? That's telling you that the cat's not working, too. Pre-cat lambda is used to adjust fuelling, post-cat lambda is used to monitor the cat.

If you were getting the post-cat lambda fault, but the emissions were correct, then the post-cat lambda would be suspect.

The fault code is po420, how much do one of these buggers cost to replace in labour lol. I think I should probably do it myself if I can and hope the corrosion not too bad 

As expected - P0420 is post-cat lambda reading is off.

Cat's in the manifold, for fast heat-up.
https://www.cats2u.co.uk/vauxhall/34804-vauxhall-zafira-18-04-05-12-10-catalytic-converter-vx6080t.html
plus a couple of hours labour or so, depending on how reluctant the manifold studs on the head are.

Clearing the fault code for the last few years has been ignoring the actual fault. Now it's got to the point you can't ignore it any more.

321p123

Thanks all, I found this on ebay, https://www.ebay.co.uk/itm/325587874994?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=Fo8EMM7ASj2&sssrc=4429486&ssuid=xfy8NKJzSw-&var=&widget_ver=artemis&media=COPY


Would you recommend or spend a bit more for a better part.

facade

I'd fit the cheapest, eBay ones don't last.

I take it yours is a late zafira?

The early one takes the £130 part, that is the one we had and it burnt oil like a VW (or an early BMW mini)!

321p123

facade said:

I'd fit the cheapest, eBay ones don't last.

I take it yours is a late zafira?

The early one takes the £130 part, that is the one we had and it burnt oil like a VW (or an early BMW mini)!

It's a 2008 with 123k on the clock, you reckon the cats2u one is best? Will only keep the car another year or two I think