Cammed VTR emissions.

26th August 2010, 15:08

Last week i failed my MOT on emissions.
The car has the 8V 1.6 engine with a newmans PH3 camshaft.
It had a decat exhaust and it failed.
I just had it retested with a new cat in place, and it failed again on emissions.

The garage told me the first thing to try is the lambda sensor.

I'm thinking the cam is probably the reason it's failed..

Does anyone have any suggestions?

Thanks in advance.

26th August 2010, 15:34

When was the last time it was serviced? Check the lambda as well.

I doubt its the cam mate, loads of people have cammed lumps that pass emmisions.

26th August 2010, 15:59

Could try diagnostics first mate to see if it is sensor related, don't just buy a sensor because you've been told it may be that, yer it could well be the lambda but it may not, it could like the chap above said just needs a good service, you never know tbh mate

How ever it certainly won't be the fact it's cammed, I ran a s1 rallye head with newmans ph2 cam which will be a higher profile than your cam, and I had an s1 inlet on too, the cat I used looked like it was either the original or a good few years old, and it still passed with flying colours and that was at Peugeot specialists and wasn't being friendly either, so it won't be that

How ever I just notice you are only based in Loughborough, I am in leics very regularly as my gf lives there, and I have top of the range diagnostics, if you want I can have a quick look for you? Say £25? I know alot of garages in leics charge £45-£50 minimum for a proper reading, and lambda will set you back 50-60quid for a decent one when it may not be that

Let me know if your interested

26th August 2010, 16:14

Hey, thanks for the replies guys!

Just been to pick the car up, it's over on CO2 and Hydrocarbons readings.

It's only just been serviced maybe a month ago.

I talked to the mechanic and some ideas i've had are..
The rocker cover breather isn't attached to the inlet at all, it's just venting into the air..
The exhaust is leaking a little at the manifold, so this could possibly give incorrect lambda readings?
Also the lambda sensor itself.. but only as a last resort

And Chris, thanks for the offer, but i'm away working for the next three weeks, and i'm up in yorkshire at the moment. Been travelling around a lot with work all summer!

Going to put another gasket on the exhaust manifold and plumb in the rocker breather.. see if that'll help!

26th August 2010, 16:21

Right tbh the breather from rocker ignore that one, many people have just run a separate filter on there and makes no problems, that's mainly for cold start up iirc
Th manifold gasket, I wouldn't have thought it would effect the emissions, I could be wrong though but never heard that one before, how ever if it is blowing will be best to change it anyway
But be carefully which manifold gasket you get as there are two types on the 8v, you can get a metal one which seals shite, a friend of mine had this problem and so did I, there is also a fabric type of material which seals alot better and doesn't need exhaust paste either, I know this cause I work for a motorfactor lol and I always search for shit like this, I did have the part number some where but can't remember where lol I'll see if I can dig it out for you to make things easier for you

26th August 2010, 16:26

That would be good actually.. the exhaust has been annoying me

I've heard some people find the manifold seals better with two metal gaskets..

I've got a spare lambda sensor here, and a second exhaust gasket, so i'l going to get them on anyway.

One thought i had was the valve clearances need doing.. it's quite tappy at the moment..

For CO2 i think the limit was .3% and i was at .6%...
I was at 4% without a cat

Thanks for the help mate

26th August 2010, 16:30

Mg2302 I think is the part number, but when you go to motorfactor say that's a BGA part number, they may cross reference it, and if they do ask them to double check wether it's a metal type, or like a fabric

Hope that helps

26th August 2010, 16:36

Yer valve clearances may be helping it fail a little tbh mate, they are dead easy to set, just remember to go by newmans clearances or it will miseries and run shit lol

If you've got another lambda to Try though, that's ace try that since u have one

Yer that is strange on the gaskets though, my mate used metal one on his rallye before he went 16v lol and we used shit loads of paste and there was just a big gap between mani and head that it wasn't sealing, used the fabric one and sealed perfectly without paste, I had same prob on my vtr, an it looked messy to with all the paste lol

Haha that's not too far put though, Find it funny how you get better emissions without cat

26th August 2010, 16:36

Cheers mate, I'll look into it when i'm back home next!

Probably report back mid september if i fail again

Thanks for the replies guys!

26th August 2010, 17:42

A leaking exhaust will definitely affect the readings too.

26th August 2010, 18:41

Quote:

Originally Posted by LeeumH

A leaking exhaust will definitely affect the readings too.

I thought that..
If air gets in.. lambda readings will be wrong.. and engine gets confused!

Exhaust shouldn't leak now.. got it all sealed up really good.
Gunna do the valve clearances when the engine cools down a bit more

26th August 2010, 21:20

i would bang a cat back on it for mot purposes 10 min job really

26th August 2010, 21:33

Quote:

Originally Posted by stendog

i would bang a cat back on it for mot purposes 10 min job really

Yeh, i borrowed one from a mate.. and it's still over

I've changed the lambda sensor, resealed the whole exhaust, and adjusted the valve clearances.. Pretty much all i can do for now.
I'll get it tested for emissions before the MOT, and if it still fails i think i'll put two cats on it

26th August 2010, 21:38

Is it the co2 reading or lambda reading it failed on

26th August 2010, 21:39

Quote:

Originally Posted by DansexysaxoVTS

Is it the co2 reading or lambda reading it failed on

CO2 and hydrocarbons.
Lambda was fine.

26th August 2010, 21:41

replaceing the cat should make it pass have you got a big bore exhaust on it ma
8

26th August 2010, 21:59

Hey, I'm kinda new here maybe a leaking gas cap is preventing the fuel tank to establish the proper positive pressure levels ? Does pressure hiss out when u take cap off ?

I work on more expensive cars so maybe this wouldn't effect a saxo as much. lol

( i have S1 106 16V turbo Track car)

26th August 2010, 22:10

if you have a big bore exhaust hold a bit of rag over it so there is a little gap or put the standed rear box on i had to do this with the rap and mine passed

26th August 2010, 23:47

Connecting oil breathers back to airbox might help a little bit?

Get the CAT nice and hot before the re-test too.

27th August 2010, 00:10

Quote:

Originally Posted by DansexysaxoVTS

replaceing the cat should make it pass have you got a big bore exhaust on it ma
8

It's got a brand new cat on it mate.
Not a big bore exhaust really, It's a magnex system and a raceland manifold..

Quote:

Originally Posted by antonyr123

Hey, I'm kinda new here maybe a leaking gas cap is preventing the fuel tank to establish the proper positive pressure levels ? Does pressure hiss out when u take cap off ?

I work on more expensive cars so maybe this wouldn't effect a saxo as much. lol

( i have S1 106 16V turbo Track car)

I haven't noticed anything like this..

All the pipework is in place for the fuel tank vapours... and i don't think it can have gone wrong on a 2003 car.

Quote:

Originally Posted by LeeumH

Connecting oil breathers back to airbox might help a little bit?

Get the CAT nice and hot before the re-test too.

The mechanic said it'd be a good idea to reconnect the breather. Cant hurt can it?

I did notice... they did two tests for emissions, and the first test (presumably from cold) showed much higher emissions than the second.
I might just make them do it as soon as i bring the car in, rather than leaving it with them for the day..

27th August 2010, 00:21

Quote:

Originally Posted by gsavill90

I did notice... they did two tests for emissions, and the first test (presumably from cold) showed much higher emissions than the second.
I might just make them do it as soon as i bring the car in, rather than leaving it with them for the day..

I've forgotten the technicalities, but I'm pretty sure the oil vapour going back through the inlet 'weakens' the fuel/ air mixture a tad. Should pass with the breather filter, but every little helps.

Try and take it for a spirited drive and then get the emissions checked as soon as you get back.

27th August 2010, 15:50

Quote:

Originally Posted by LeeumH

I've forgotten the technicalities, but I'm pretty sure the oil vapour going back through the inlet 'weakens' the fuel/ air mixture a tad. Should pass with the breather filter, but every little helps.

Try and take it for a spirited drive and then get the emissions checked as soon as you get back.

Always hard to get a spirited drive in at half eight in the morning

I'll ask them to test it whilst i wait though, so it's not sat there all day..

I'll plumb the breather back in.. cant hurt can it?
The mechanic seemed to think it'd help emissions.. I think i heard it was emissions related somewhere.. dunno though.
Away working now, but i've booked it in on the 16th of september.. so fingers crossed!

16th September 2010, 11:50

Right, just got it retested for the forth time!

I had the manifold with the cat in, a cat in the centre pipe and a new lambda sensor in...
Still failed.

The guy at the garage recons the cam needs to come out... Fun times!

11th November 2010, 20:24

Right.. just for reference...

With two cats... and a PH3 cam.. i was getting at least 4/5 times the CO2 limit. And hydrocarbons were well out too.

Took the cam out.. got it retested, and everything was at pretty much 0.

Wouldn't have cammed it if i'd known it wouldn't pass an MOT..