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zarosfaltor
04-05-2017, 12:50 AM
Having some trouble passing CA emissions on my 95 525i, when I took it in initially the numbers were failing across the board:




%CO2

%O2


HC(PPM)



CO(%)



NO(PPM)





Test

RPM

MEAS

MEAS

MAX

AVE

MEAS

MAX

AVE

MEAS

MAX

AVE

MEAS

Results



15mph

1706

13.9

0.5

81

23

241

0.47

0.08

0.64

683

194

1356

FAIL



25mph

1867

14.6

0.0

46

14

96

0.44

0.06

0.26

692

166

240

FAIL





Replaced out the O2 sensor, first shop was having trouble with their test machine, so I took it to a different place. The car almost passed, only missed the 25mph HC by 1ppm:




%CO2

%O2


HC(PPM)



CO(%)



NO(PPM)





Test

RPM

MEAS

MEAS

MAX

AVE

MEAS

MAX

AVE

MEAS

MAX

AVE

MEAS

Results



15mph

1658

14.7

0.0

81

23

70

0.47

0.08

0.05

683

194

147

PASS



25mph

2856

14.7

0.0

46

14

47

0.44

0.06

0.15

692

166

155

FAIL





Since I had a free retest at the first place, I had them test it again as well and got similar results (only failing 25mph HC):




%CO2

%O2


HC(PPM)



CO(%)



NO(PPM)





Test

RPM

MEAS

MEAS

MAX

AVE

MEAS

MAX

AVE

MEAS

MAX

AVE

MEAS

Results



15mph

1705

14.9

0.0

81

23

68

0.47

0.08

0.07

683

194

96

PASS



25mph

2871

14.9

0.0

46

14

54

0.44

0.06

0.12

692

166

143

FAIL





Car has had the spark plugs, fuel filter, and air filter all replaced relatively recently. Cooling system was also recently redone. Car idles and runs great before and after replacing out the O2 sensor. Could the cat have just finally started to give up, or does anyone have any ideas to try since it's so close?

mottati
04-05-2017, 01:15 AM
i'd throw fresh oil and filter in, and run some cataclean or other 'guaranteed to pass' stuff in. That's so close.

GregT53
04-06-2017, 01:41 AM
Check to make sure your spark plugs are torqued to spec. I've had them work loose, and this can adversely affect emissions results.