NCT Fail - High Idle Emissions

Mister Man

Have a 2000 Honda Civic. Thought it would have passed the NCT today, but turns out, I was wrong.
It failed on bushes on the back, which is fine, I know how to fix it.
It also failed on high idle emissions.

Lambda : 0.98 (Passed)
CO : 0.67% (Failed)
HC : 225 ppm (Failed)

The car was tested from cold, as I left it there, rather then waiting weeks to have it booked.
I recently replaced the cat converter, and had the back-box welded by a mechanic as it had a little hole in it. I've seen people posting about Dipetane, and how it fixed it for them. Would this work? Or am I looking at a costly fix..?

Thelostcountry

the Car tested from cold needs to be up to manu running temp! what temp does it say on fail sheet??

Mister Man

Thelostcountry wrote: »

the Car tested from cold needs to be up to manu running temp! what temp does it say on fail sheet??

Don't have it to hand right now, but I mean it was left outside in the rain for 3-4 hours before they took it for a test. So no chance the Italian tune-up would help me.
I've looked around, and the answers seem mixed. Some say it could be the Lambda / O2 sensor - Others just say just the stuff mentioned above and rev the ****e out of the engine before bringing it in. Some even say that the exhaust could be leaking somewhere, which would be odd, seeing as the mechanic charged me for fixing leaks just last week.

jetfiremuck

Change oil and filter, make sure pcv valve is clean,ensure plugs and wires are good check timing.

Mister Man

jetfiremuck wrote: »

Change oil and filter, make sure pcv valve is clean,ensure plugs and wires are good check timing.

Will give that a go. I'll book it in for a re-test next Friday, and get that done over the weekend

Chimaera

Cold engine's to blame here I think. If the car's recently been serviced there's no point doing it again. You're only slightly out on HC and a bit out on CO, both of which could result from a cold engine. If the plugs have not been recently changed, then I'd do this. Other than that, take it for a good drive for 30-40 minutes just before the test and it'll probably be ok.

Mister Man

I'd say it could do with new plugs. Guy I bought it from said its due a service soon. On 144k. Last done at 130k give or take.
I'll book it's re-test tomorrow and get new plugs while I'm picking up the new bushings. I'll give it a good drive this time around, as it'll be actually booked for a certain time now. I assume give it loads of revs?
Thanks for the help lads! I was worried it was a major problem! It's total cost will come to <€700 should be able to make a few quid off it

Chimaera

At 14000 miles since its last service, you could probably do oil and filter on it. I was assuming it'd been done much more recently than that.

corkgsxr

Chimaera wrote: »

At 14000 miles since its last service, you could probably do oil and filter on it. I was assuming it'd been done much more recently than that.

Id have done plugs oil and filters twice in that miles.

Mister Man

corkgsxr wrote: »

Id have done plugs oil and filters twice in that miles.

Only bought it three or four weeks ago. Haven't driven it more then a couple miles.
I'll get a full service done on it while it's in for the bushings. No harm anyway. It's only 100 odd quid.

nct tester

For a car to fail petrol emission test it has to go through a process whereby its held at at least 2500 rpm for a minimum of 5 minutes and it doesn't matter if the car comes in after being parked out in the snow for 2 days, it will be well hot after 5 minutes of >2500rpm. Changing the plugs wont make much difference unless they are sooted up. Have a look at he link to give you an indication of how healthy your combustion process is.

http://www.google.ie/imgres?imgurl=http://www.hayabusa.org/forum/attachments/maintenance-do-yourself/116966d1223649221-spark-plug-condition-reference-pics-scan10001_edited.jpg&imgrefurl=http://www.hondaatvforums.net/forums/performance-modifications/18995-programmer-best.html&h=800&w=786&sz=131&tbnid=N0aPQnsaj2dNeM:&tbnh=93&tbnw=91&zoom=1&usg=__5o374ymyBa48qrmCzKdFLyTjZu8=&docid=Oy--a1vM1RkKkM&sa=X&ei=Cmp9UpbyLsHW7QbYkoBQ&ved=0CDIQ9QEwAg

Also at those readings dipetaine wont make a difference, it may, and i emphasise may, help if your CO readings are only ever so slightly over the limit. Another thing is, try bring it to a mechanic who has an emission tester because getting him to do work will cost you, then getting nct to test it is another €28. If your mechanic has no emission tester, he has no way of knowing if the work he had done was needed. Why did he change the cat in the first place??

Mister Man

nct tester wrote: »

For a car to fail petrol emission test it has to go through a process whereby its held at at least 2500 rpm for a minimum of 5 minutes and it doesn't matter if the car comes in after being parked out in the snow for 2 days, it will be well hot after 5 minutes of >2500rpm. Changing the plugs wont make much difference unless they are sooted up. Have a look at he link to give you an indication of how healthy your combustion process is.

http://www.google.ie/imgres?imgurl=http://www.hayabusa.org/forum/attachments/maintenance-do-yourself/116966d1223649221-spark-plug-condition-reference-pics-scan10001_edited.jpg&imgrefurl=http://www.hondaatvforums.net/forums/performance-modifications/18995-programmer-best.html&h=800&w=786&sz=131&tbnid=N0aPQnsaj2dNeM:&tbnh=93&tbnw=91&zoom=1&usg=__5o374ymyBa48qrmCzKdFLyTjZu8=&docid=Oy--a1vM1RkKkM&sa=X&ei=Cmp9UpbyLsHW7QbYkoBQ&ved=0CDIQ9QEwAg

Also at those readings dipetaine wont make a difference, it may, and i emphasise may, help if your CO readings are only ever so slightly over the limit. Another thing is, try bring it to a mechanic who has an emission tester because getting him to do work will cost you, then getting nct to test it is another €28. If your mechanic has no emission tester, he has no way of knowing if the work he had done was needed. Why did he change the cat in the first place??

Very helpful reply. Greatly appreciated!
The cat was changed, as the guy I purchased it off was told it fecked. I have my doubts about that now, but no harm in having it I guess.
The mechanic that's changing the bushings also has an emissions tester (or did a year ago), so he should be able to sort it. Should I pull one of the plugs out myself and see if it's is ****e, or will I just leave it for him?

nct tester

Id just leave it to him to sort out if he has an emission tester. Its also possible the car has failed a few times on emissions and thats why the previous seller was selling it on. With a hc reading like yours its possible your car is burning oil and its definitely running a bit rich.

JohnBoy26

14k since the last service :eek: Hondas of that vintage need fresh oil and filter ever 6k miles:)

Mister Man

Had the Civic re-tested today. To my surprise, it failed on the emissions again! No movement from previous test!
Bushings were changed the other day, and the mechanic rang me a day later, telling me the axel bushings needed to be changed also. Cost quite a bit, and needed to be re-aligned afterwards. He also told me he gave it an emissions test, and added two bottles of stuff similar to Dipetane, designed to lower the specific emissions it had failed on. He also changed the oil, plugs, and filters. I also added Dipetane previously, as it was only a tenner in the garage. Car was given a good, hard drive before going in, so engine was red hot at this point.
I've no idea were to go from here. I've paid way more then I care to admit on getting everything ready. I'm a bit annoyed that I was charged for emissions work/test when the emissions didn't change at all. Anyone have any other suggestions? I'm assuming the next option is re-building the engine or replacing it, but it's no an option for me. Cost will be too much for me.

Chimaera

Can you post up the full results?

Mister Man

Chimaera wrote: »

Can you post up the full results?

Here's the fail sheet (previous and new) along with invoice.
Invoice from Mechanic -


Previous fail sheet -


Today's failed sheet -

Something causes it to overfuel (lambda below 1 is rich) and the result seems consistent. There should be a vacuum line going to the fuel pressure regulator. Is the connection solid? If not or if missing altogether would cause too high a fuel pressure at low load which would make it hard for the ECU to keep emissions under control. It could also be a map sensor or vacuum line to it or air flow meter fault depending on which the engine management uses.

So check all the vacuum lines first and see if that helps.

MercMad

Looks like a lazy O2 sensor to me. What he has done has dropped it a little. Also if your CAT was gone previously a bad O2 sensor could have caused it.

Mister Man

MercMad wrote: »

Looks like a lazy O2 sensor to me. What he has done has dropped it a little. Also if your CAT was gone previously a bad O2 sensor could have caused it.

Cat was recently changed. Had my suspicions myself about the O2 sensor. Will get that look at.

samih wrote: »

Something causes it to overfuel (lambda below 1 is rich) and the result seems consistent. There should be a vacuum line going to the fuel pressure regulator. Is the connection solid? If not or if missing altogether would cause too high a fuel pressure at low load which would make it hard for the ECU to keep emissions under control. It could also be a map sensor or vacuum line to it or air flow meter fault depending on which the engine management uses.

So check all the vacuum lines first and see if that helps.

I'll be home in a bit, and will have a look at this.
Cheers for the help lads! Thought it was fit to the scrap yard