NCT emissions - High Idle

Shakti230

My clio failed the nct on emissions, the high idle failed.

Lambda was .91 should be between .97 and 1.03
CO was 3.21 shouldnt be above .30
HC was 237 ppm shouldn be above 200 ppm.

Any ideas on what it needs to fix it? Would changing the lambda sensor make any difference?

Any ideas appreciated!!

shamwari

Shakti230 wrote: »

My clio failed the nct on emissions, the high idle failed.

Lambda was .91 should be between .97 and 1.03
CO was 3.21 shouldnt be above .30
HC was 237 ppm shouldn be above 200 ppm.

Any ideas on what it needs to fix it? Would changing the lambda sensor make any difference?

Any ideas appreciated!!

Where those figures @ idle or fast idle? Are there no misfires with the car or holes in the exhaust?

Shakti230

How can I tell if it is idle or fast idle? On the nct sheet it says High idle (2840rpm) and then my results:

Lambda was .91
CO was 3.21
HC was 237 ppm

The low idle passed.

It is not misfiring and te exhaust was checked recently enough. Can get it checked again, is there anything else I would need to get checked?

Thanks!!

shamwari

Could be a number of things, but o2 sensor would be likely. Best thing to do would be to get someone with a scanner to read the o2 sensor signal to see if it is switching properly.

Have the car nice and hot for the retest too!!

biko

If the CO is very high and the HC is close, then you may have a timing/mixture problem. Read this

Shakti230

Thanks for all yer help, will check those things out!

Cheers