Wits end CO Emissions

[cavalier1990]

Hi Guys

Cavalier 1.8 M Reg 90k Miles well looked after

Replaced CAT couple of weeks ago as my emissions last year were a bit high - actually failed but guy knew me and let me go. So this year thought everything would be fine, and it was until emission test. It failed on high idle CO, value is triple what it should be, said it should be about 0.20 but mine are up high 70s

When he was moving the car from the ramp I heard a slight fart from the manifold - can it be a leak in the exhaust causing it? Last year we put 2 fuel cleaners through it, one of them down the throat and it made no difference so I am sceptical to go down this route again - they are about ten pound a pop.

Sensor is quite new as well and the catalyst is new although is not OE.

Car runs fine and doesn't seem to use a lot of fuel.

I did change the gearbox to manual over a year ago and wonder if I done something that has screwed up a connection to the ECU or something, I remember having to short out a few plug pins on the bulkhead after box swap (as per instructions) and maybe is this causing it? Although I don't notice any running problems.

Otherwise I am stumped, in fact i'm stumped full stop!

Andy

[cavalier1990]

Also does anyone know the ohm value reading of the temp sensor cold/warm?

[btcctroy]

Try a new lambda and cts sensor

[cavalier1990]

Try a new lambda and cts sensor

lambda is quite new and going to try CTS when I can get one? I looked at the sensor plug and the pins looked slightly off colour like water had got in so I gave them a WD40.

[btcctroy]

Most auto shops should should have one in. Could be reading to cold so just change it rather than mess about with the old one. About 15quid

[cavalier1990]

I was under the imperssion the CTS was at the back next to the alternator but according to the VX parts guy it's the one on the rad? Is this correct? If so what is the one at the back of the engine, mine's is blue in colour?

[Gaz]

its not on the rad, thats the rad temp switch.

Your right.

[cavalier1990]

its not on the rad, thats the rad temp switch.

Your right.

Ok thanks I thought so

Get the parts on Tuesday and see how it goes, meanwhile am cleaning out the breather system and changed the oil plus put a fuel cleaner through it.

[planetc]

I was under the imperssion the CTS was at the back next to the alternator but according to the VX parts guy it's the one on the rad? Is this correct? If so what is the one at the back of the engine, mine's is blue in colour?

Tell him he is a pratt

[cavalier1990]

I was under the imperssion the CTS was at the back next to the alternator but according to the VX parts guy it's the one on the rad? Is this correct? If so what is the one at the back of the engine, mine's is blue in colour?

Tell him he is a pratt

I'm convinced the training manual for parts guys now has this one sentence in it and that's all they need to know:

There's two different types for that on your car and we can't tell from our highly sophisticated computer system in combination with your registration and VIN No what one it is!

give me an old school parts guy any day

[btcctroy]

Replace the blue one at the back of engine. If its still burning rich check all plugs

[iancav6]

Try disconnecting the battery to reset the ecu back to default settings.Worked on Daughters Focus when that kept failing.

[humbucker]

Try disconnecting the battery to reset the ecu back to default settings.Worked on Daughters Focus when that kept failing.

Maybe she should have gone to an optician?

[planetc]

Try disconnecting the battery to reset the ecu back to default settings.Worked on Daughters Focus when that kept failing.

Maybe she should have gone to an optician?

That was a bit complicated...took me ages to figure that one out!!

[iancav6]

Try disconnecting the battery to reset the ecu back to default settings.Worked on Daughters Focus when that kept failing.

Maybe she should have gone to an optician?

You should be on Britains got talent.

[cavalier1990]

Ok here's what I done yesterday:

fixed manifold slight leak - had two bolts missing on manifold to downpipe join, one was bust had to heat it to get out, also new manifold and downpipe gasket
New temp sensor
Oil flush and change

And took it in this morning and failed again, the reading was still more or less the same so as you can imagine slighty aggrieved

So I spoke to an a mechanic I used to work with and he said have you changed plugs and air filter, which i've not, although usually give the air filter a bash against a wall and the plugs a wire brush now and again, and they always look clean and never sooted up. He said doesn't matter that is a big thing with the cavaliers failing emissions.

So going to get the plugs today and filter and pray to the big guy up the stairs he can get me through.

Question: Anyone know where the EGR valve is on the cav? According to this ad there is but I ain't seen it in my travels:

http://www.amazon.co.uk/Vauxhall-Cavali ... B009KPOSPO

[cavalier1990]

I also tried the paperclip test and it is continually flashing, what does that mean? No placeholder 12 or anything it just starts flashing and doesn't stop.

[cavalier1990]

Bump - any ideas on the paperclip test guys? Also I see now the EGR valve is this worth cleaning out/would it cause such an issue as high CO readings if it was blocked up etc.?

Thanks

Cav

[iangsi]

Question: Anyone know where the EGR valve is on the cav? According to this ad there is but I ain't seen it in my travels:

The EGR valve is located between the back of the cam cover & in front of the air box on top of the inlet manifold, if you see my thread you can the shiny blank plate where I removed mine, see here 2nd pic viewtopic.php?f=22&t=5939

[cavalier1990]

Question: Anyone know where the EGR valve is on the cav? According to this ad there is but I ain't seen it in my travels:

The EGR valve is located between the back of the cam cover & in front of the air box on top of the inlet manifold, if you see my thread you can the shiny blank plate where I removed mine, see here 2nd pic viewtopic.php?f=22&t=5939

Hi Ian

For what reasons did you remove it, was it an emissions problem and did it sort the problem?

Cav

[iangsi]

Question: Anyone know where the EGR valve is on the cav? According to this ad there is but I ain't seen it in my travels:

The EGR valve is located between the back of the cam cover & in front of the air box on top of the inlet manifold, if you see my thread you can the shiny blank plate where I removed mine, see here 2nd pic viewtopic.php?f=22&t=5939

Hi Ian

For what reasons did you remove it, was it an emissions problem and did it sort the problem?

Cav

I removed it because I thought it was causing my engine to idle very rough & lumpy causing high emmissions at MOT time, but it drove perfectly with the advice of some on here, but turned out to be an air leak on the rigid pipe on the right hand side of the inlet manifold. It has some other benifits as well such as slightly better throttle response. there is a thread on here some where about removing the EGR valve & all the benifits. hope this helps you out.

[cavalier1990]

The EGR valve is located between the back of the cam cover & in front of the air box on top of the inlet manifold, if you see my thread you can the shiny blank plate where I removed mine, see here 2nd pic viewtopic.php?f=22&t=5939

I removed it because I thought it was causing my engine to idle very rough & lumpy causing high emmissions at MOT time, but it drove perfectly with the advice of some on here, but turned out to be an air leak on the rigid pipe on the right hand side of the inlet manifold. It has some other benifits as well such as slightly better throttle response. there is a thread on here some where about removing the EGR valve & all the benifits. hope this helps you out.

Thanks I also found a crack in my servo hose today and replaced it, must be common problem with these, and it's one of those things you press against when you lean into the engine bay so that probably breaks it.

[cavalier1990]

So after all the work i've done (top end overhaul/new cat/fixed servo leak/service) it still failed emissions although seems to be a bit less than before. When on tickover the lambda goes up too high, co seems to come down, opposite on high idle test, so the tester was trying to balance it in between with revs but not working.

I'm going to another garage for a second opinion and am putting cataclean through it.

After doing the work on it it seems to be running really good, there's a marked improvement in pick up and I would say i've probably got another 10 BHP after overhauling the head.

[planetc]

high idle lambda suggests air leak?

[cavalier1990]

Got the 2nd opinion today on the emissions and it is this: Stumped

The guy said the emissions are so near yet so far and he cant see anything at all that would lead him to think there is an issue except obviously the emissions reading; which is high CO and lambda. He thought it was strange that both lambda and CO were high - would be one or the other - however to add to the story it was lamdba = high at tickover and CO high at fast idle on the previous test not at same time!

Long and short of it is the guy said try another injector, it's "worth a punt"

Deviating away from specifics I am going to see an old mate from the trade who has told me to contact him if I am still having problems. Going to see if he can "Pass" it for me!