E36 Emissions...

This is the only thing my 318is failed on in the NCT,

NCT RESULTS:

Engine/Oil temp: 107'C

Low Idle: CO .63vol%
HC 214ppm
Lamba: .98

High Idle: CO .64vol%
HC 86ppm


Got a new Cat and a Lamba fitted and got emissions checked, New readings are: (Taken at idle)
C02 %VOL 13.39
HC PPM. E08
02 %VOL 1.52
C0 %VOL 1.067
C0cor %VOL 1.11
Lambda. 1.014

Then swapped in an Air-Flow meter from my other 318is, and readings were:
C02 %VOL 9.97
HC PPM. 437
02 %VOL 7.04
C0 %VOL .461
C0cor %VOL .66
Lambda. 1.409

What do people make of the results?
If I'm reading it right, The latest results are NCTable except for Lambda result?

Any help at all is welcome, Would be nice to get an NCT on it.

I am curious to see if anyone can shed some light on this as well. I'd be a bit stumped at this point too. I would have done what you have done.

What's the engine like? Any issues at all that might be contributing?

I'm sure you've been using it but dipetane?

I got something like 0.01 after a good dose, redened her and straight into be tested with no waiting.

Failed or failing coolant temp sensors can up the emissions a bit, should be one under the inlet manifold connected to the cylinder head

Engine is sweet, Although it does seem heavy on petrol and you can smell it when you start it when it's been sitting a few days. It has about 181,600 up. (3k since previous NCT)

Have Oil/Filter, So I'll service it next although it should be okay.

I'll try the temp sensor and see, I'v a spare one here.

Should have also added failed or failing cam and Lambda sensors will play havoc with the emissions and also fuel consumtion as will the temp sensor, get the codes read to be sure

I've just had the same thing happen
low idle CO 0.77%
High idle CO 0.71%
It's had a new cat and a recent service
Any ideas would be welcome
It's an M43

Still not done anything about this. :/
It's not showing any error codes either.

Anyone any idea of what else would effect emissions besides Cat/Lambda?

I'm very curious, who told you to change the CAT? It's a bit drastic.

High Lambda= a hole, you'll find it hard to find as it's one that's sucking in air, it's called a venturi, the exhaust flowing at speed will suck air in any holes, see your results..the Lambda increases when the REVs to, (or speed of exhausted gasses)
your HC is very high for a new CAT, are you sure it was at temp? CATs burn off HC when they are at temp(and working).

Normally, to fix the HC on an aging BM,
remove and thoroughly clean your air intake, ALL of it. The throttle will have heavy deposits of burned oil, like TAR. On the manifold side so it needs to come off......
put in a new air filter.

After that and putting it all back together, you have to look around for an air leak, unmetered air will cause havoc with the air/fuel mix.
Go after your rocker cover breather pipe first!

Temp sensors are also a killer, it'll not show on any static diag, only a dynamic one.
Just change them, about 20-30euros for 1.

Quote:

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Originally Posted by seanmul

I'm very curious, who told you to change the CAT? It's a bit drastic.

High Lambda= a hole, you'll find it hard to find as it's one that's sucking in air, it's called a venturi, the exhaust flowing at speed will suck air in any holes, see your results..the Lambda increases when the REVs to, (or speed of exhausted gasses)
your HC is very high for a new CAT, are you sure it was at temp? CATs burn off HC when they are at temp(and working).

Normally, to fix the HC on an aging BM,
remove and thoroughly clean your air intake, ALL of it. The throttle will have heavy deposits of burned oil, like TAR. On the manifold side so it needs to come off......
put in a new air filter.

After that and putting it all back together, you have to look around for an air leak, unmetered air will cause havoc with the air/fuel mix.
Go after your rocker cover breather pipe first!

Temp sensors are also a killer, it'll not show on any static diag, only a dynamic one.
Just change them, about 20-30euros for 1.

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The cat that was in it was empty, Cat is a new MotorFactor job and car was driven hard for 7/8 miles before checking results so was well up to temp.

Seems to be a slight smell of petrol sometimes when it's running?


Thanks for the help BTW! :)

it is more than easy to check if u have any leaks or holes on ur exhaust. just keep wet rag against it, if the exhaust is good and hole less u wont be able to hold the rag, if there will be any minor holes, it will start wistling, you will hear it right away if something is wrong.
something is telling the car to over fuel. as mentioned before it can be temp sens. temp sens would not pull an error, it would show something and car would thing its still cold and give her more fuel than it needs

Quote:

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Originally Posted by armando

it is more than easy to check if u have any leaks or holes on ur exhaust. just keep wet rag against it, if the exhaust is good and hole less u wont be able to hold the rag, if there will be any minor holes, it will start wistling, you will hear it right away if something is wrong.
something is telling the car to over fuel. as mentioned before it can be temp sens. temp sens would not pull an error, it would show something and car would thing its still cold and give her more fuel than it needs

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Should be no leaks as the exhaust is new, But I'll double check anyway.

Actually just realised I'v fitted the Temperature Sensor from another car and it makes no difference.

another car? same engine? ive no AD handy now, get the corect values for it and check it with multimeter

Any joy with finding a solution on this? My 318is just failed as well for co out spec at fast idle. HC were in spec though. Trying to research what to do. Lots of similar problems when you do a search but not too many definite solutions seem to be documented.

The rubber breather hose from the pcv to the rocker cover can collapse under load if its perished on the inside, this caused my 318is to fail on high idle. It seemed fine at tickover but it felt soft in the middle and got really soft when the engine was hot.
Also my pcv valve was filthy too, cleaned it, replaced the pipe and she passed.