NCT Emissions Failure - '97 Civic 1.4

golfbgud

Just back from NCT center where they failed my wife's '97 1.4 3door Civic.

I realise it's hard to believe but it's true!

Didn't do anything with the car prior to the test just let it roll! Needs a service.

Here's the numbers:

Low Idle
CO 3.09%
HC 714ppm

High Idle
Lambda 0.81
CO 6.73%
HC 429ppm

I haven't looked at the air filter etc as yet - just checking what your feedback is.

All feedback welcome and appreciated.

Thanks.

kona

0.8% lambda means your 20% rich , your HC (unburnt fuel or oil) is off the scale IMO, Id give it a serious service, filters,plugs,leads, although I would imagine you could have a sensor / cat issue too.

golfbgud

Thanks Kona.

I forgot to mention it only has 58k miles on the car.

Plug

I'd say your car is clocked. I'd go with kona on this, replace the cat an 02 sensor.

beachlife

could be leaky injector ,bad ignition, car is running rich with a misfire,also could be tight exhaust valve clearance etc, don't buy a cat or lambda until you have tested yours.

golfbgud

Car is deffo not clocked - I am the second owner from new (bought from main dealer at 18k miles). All genuine. Won't be touching cat or sensors just yet - not convinced this is anything more than a service right now.

I'm gonna service it next week and retest emissions. It never failed any other time but didn't service it before NCT this time so took a risk. Also needs a driveshaft boot.

I did notice today that the temp gauge is running cold (unless stationary where it rises to normal). Internal heater is working but not as warm as it should be. I cannot see that this would have any effect on the Emissions but will stand corrected. Would this be the thermostat sticking open or what?

DublinDilbert

Does sound like the thermostat has failed open, when you take it onto the motor way does the internal heater work ok?

Yep the car running too cold will cause emissions problems as the ecu will add extra fuel. But if car was idling for a while at the test centre it should of warmed up.

I would put a scope or dmm onto the lamda output and see what u are getting...

golfbgud

Hmmm some good points there - thanks Dublindilbert.

Yes heater works when on long spin but not as warm as it should be. Gauge shows cold and only rises when car is stopped in traffic etc.

I was delayed for about 45mins in NCT centre (something to do with staff changeover) so it looks like this didn't help my cause because it probably went cold and then auto choke kicked in etc.....makes sense now based on your feedback!

Changed oil and filter yesterday. Air filter and plugs need replacing so I will do that next week along with thermostat.

DublinDilbert

I'm not overly familiar with a golf of that era, but chances are it's not running in 'closed loop' till it's warmed up...

TURRICAN

was the engine oil temp up to 80degrees when it was being tested,if not bring it back and get them to retest for free.

golfbgud

TURRICAN wrote: »

was the engine oil temp up to 80degrees when it was being tested,if not bring it back and get them to retest for free.

Yes - checked Cert again today and it reads 90c so I guess it was a legal test.

Thanks.

shamwari

golfbgud wrote: »

Yes - checked Cert again today and it reads 90c so I guess it was a legal test.

Thanks.

That's probably the oil temp. If you feel that car is not as warm as it should be then get the thermostat checked. Hopefully that is all that's wrong.

THOMAS TYRRELL

a service dosent sound like a bad idea but wont always have a major impact on emmisions. after a service if your emmisions still arent 100% try a bottle of dipetane(can get from any decent motor factor) and let flush through fuel system for a week or so and then have your emmisions checked preferably after a good roasting, if this fails to work you need to seek a professionals advice.

ps. not a dipetane salesman,.. own my own garage and have used the stuff myself in the past with very good results.

tom

golfbgud

Mechanic fitted a thermostat last night and that has fixed the heating/cooling problem (car is now nice and warm)!

Oil, Oil Filter, Plugs and Air Filter all replaced.

Should I chance the NCT or get the emmissions checked beforehand? How much typically will I expect to pay a local garage to do a test (my mechanic does not have the equipment)?

Thanks All.

shamwari

A retest on the NCT will probably be cheaper than bringing it to a emissions tester elsewhere !

golfbgud

NCT Pass!

I put it down to a service and the replacement of a sticking thermostat. No dipetane or any other additives used.

Result!

Plug

Result!
I thought it was going to be the cats fault, looks like the old plugs weren't up to the job maybe. What were your HC's reading with the NCT pass?

golfbgud

Plug wrote: »

Result!
I thought it was going to be the cats fault, looks like the old plugs weren't up to the job maybe. What were your HC's reading with the NCT pass?

Low Idle HC 26ppm 0.15%
High Idle HC 29ppm 0.12%

Lambda 1.00