Is200 NCT fail emissions fail, 2nd time

Kusiek

Hi, I've put my is200 through NCT second time and it failed on emissions again.

The first time it went through NCT it had engine light on, codes:
P0141 O2 sensor heater circuit bank 1 sensor 2 and P0136 O2 sensor circuit bank 1 sensor 2

Emissions results:

Engine/Oil temp 92°C
Low idle CO 0.03% PASS
(630 rpm) HC 16 ppm N/A
High Idle Lambda 1.12 Not between 0.97 and 1.03 MAJOR
(3,080 rpm) CO 0.05 vol% PASS
HC 6ppm PASS

Mechanic told me he fixed the O2 sensor issues and did fuel system treatment, went to do the NCT and it failed again on emissions.

Engine/Oil temp 0
Low Idle CO 0.12 vol% PASS
(630 rpm) HC 59 ppm N/A
High Idle Lambda 1.09 MAJOR
(2,890 rpm) CO 0.86 vol% Above 0.30% MAJOR
HC 103 ppm PASS

Guy that was testing it told me there are few small exhaust leaks, could this be the reason? How come the first time it passed CO and failed only on lambda and the second time it failed both High idle Lambda and CO.

blackbox

High lambda indicates too much oxygen.

Fixing exhaust leaks will probably sort it.

mk7r

blackbox wrote: »

High lambda indicates too much oxygen.

Fixing exhaust leaks will probably sort it.

What about the high CO? a lean condition with high CO is unusual. OP was it only the rear 02 that was changed?

CoBo55

Did you warm the engine up properly for the second test? The figures for the second test are very odd.