Emissions

[Phil Durn]

My Chimaera 400 has just failed the dreaded test on exhaust emissions. Can anyone offer any suggestions as to likely causes

[pk500]

how old is the car ? if its m reg or before it has to be 3.50 co or under if its n or after the cat has to work 0.30% max and 0.97 to 1.03 lamba and 200 max hc what did it fail on exactly

[Phil Durn]

Hi pk 500
Its an N reg 1995,
Fast Idle speed,CO 4.66%, fail. HC 179ppm, Pass. Lambda 0.87 fail.

Fast Idle speed,CO 4.58%, fail, HC 141ppm, pass, Lambda 0.87, fail.

Natural Idle speed, CO 5.19%, fail

[GreenV8S]

From the look of that it's firing OK but well rich. Could be a coolant sender problem (measure the resistance to check) or a faulty lambda sender or some other fault pushing the ECU into fault mode.

[pk500]

I take it the cat`s are still in it. if so a lamba sensor could be at fault but there are two to choose from the hc`s are higher than normal proberbly because the co is high. also air flow meter can upset the co or a air leak a vac pipe off. does it idle ok?

Edited by pk500 on Monday 17th September 21:53