Getting my 182 through Emissions

[Rob_Willow]

Hello!

Last June (2023) my 182 passed MOT with a new ‘Cat2u Cat’

The car has done ~900 miles since, and having re MOT’ed for this year, failed on emissions.

The garage said it’s the cat. I’ve removed it and sent it off under the 2 year warranty (week 5 now, still not heard back)

I was wondering, if there is anything specific that could cause the engine to throw out bad emissions, even if this cat was working correctly?
The lambda readings are around 1 ohm each.
I Don’t want to keep throwing new cats at the car, if it’s engine is going to cause them to break up within a year?

Rob

 

[Rob_Willow]

Also to add, the car was running Shell Optimax, the mechanic tried for quite some time to get heat into the cat, plus a long drive before MOT.

 

[alistairolsen]

old/malfunctioning lambda sensors - if not replaced recently I'd replace the front one.
Defective coolant temperature sensor causing enrichment - Check with an OBD2 scanner
Poor thermostat preventing temperature reaching the correct operating range - parcel in check with above
CAT not being hot enough - You've already covered this in your second post
A leak in the intake system can sometimes cause issues, likewise a leak in the exhaust ahead of the CAT

 

[Matt Cup]

Might just be a crap cat. Try and source can oem one.

 

[botfch]

The cheap cats always end up failing, best bet is to just keep it in the garage for an mot then put a decat back in afterwards.

 

[Rob_Willow]

Thanks for the reply’s.

I’m going to install 2 new Lambda sensors and try another cat, and maybe change the spark plugs.

I’ve read that the ‘white plug’ needs attention on these, can cause lots of error codes which my OBD2 has picked up on.

It did have a small leak pre cat so maybe that was a reason it failed.. let’s see I’ll bang on a new fixing kit at the same time .

 

[JamesBryan]

Get some high temp silicone in the joints to seal it up.

They never like to seal up great at the best of times.

 

[Udder Nonce]

What did it fail on?

 

[dangerous dave]

Can't you just run 2 and take it off after

Another car group has a guy that loans out cats and various other stuff for passing emissions and things.

 

[Rob_Willow]

What did it fail on?

Emissions & rear brake lines - fixed them already

 

[Udder Nonce]

No, as in what on emissions?.

 

[Rob_Willow]

No, as in what on emissions?.

 

[alistairolsen]

Does your code scanner let you view the live data from the lambda as a graph? High CO and the lambda off scale suggests there's something funny going on with the engine/fuelling rather than just a dead cat I would think - but happy to be proven wrong!

 

[Rob_Willow]

Does your code scanner let you view the live data from the lambda as a graph? High CO and the lambda off scale suggests there's something funny going on with the engine/fuelling rather than just a dead cat I would think - but happy to be proven wrong!

I will have a look this weekend. I've ordered another cat (The ebay shop whom i returned it to 6 weeks ago have stop replying) and i cannot see a way to get it back!
I have 2 new lambda sensors to install, new spark plugs and a full oil service for good measure!
I think anything that controls the fuel/oxygen mixture, can alter emissions, good cat or not. Lets see!