failed CA smog, high NO and HC
05-19-2014, 11:51 AM
#1
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failed CA smog, high NO and HC
I recently failed smog with high NO and HC, car has 162k miles. My numbers were as follows:
HC CO NO
15mph 88 0.18 747
25mph 57 0.17 1034
my numbers from my last smog 2 years ago:
HC CO NO
15mph 2 0.05 22
25mph 1 0.00 219
I recently changed the oil, new air filter, drove the car to temp before testing. I have a vag com, although I dont know how to use it too well. It shows readiness passed, and I have no codes. The car is pulling 20 lbs of vacuum at idle. I just dont get how my numbers changed so much in 2 years with no codes. So if anyone has any ideas as to what to check, with or without vag com let me know. From what I gather from readin the ross tech manual, a lot of functions arent supported for this engine as far as readiness or sensor testing, but I may be wrong. Thanks.
HC CO NO
15mph 88 0.18 747
25mph 57 0.17 1034
my numbers from my last smog 2 years ago:
HC CO NO
15mph 2 0.05 22
25mph 1 0.00 219
I recently changed the oil, new air filter, drove the car to temp before testing. I have a vag com, although I dont know how to use it too well. It shows readiness passed, and I have no codes. The car is pulling 20 lbs of vacuum at idle. I just dont get how my numbers changed so much in 2 years with no codes. So if anyone has any ideas as to what to check, with or without vag com let me know. From what I gather from readin the ross tech manual, a lot of functions arent supported for this engine as far as readiness or sensor testing, but I may be wrong. Thanks.
05-20-2014, 09:09 AM
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yeah thats about all I can come up with as well. I dont get why it passes readiness though. Dont the post cat o2 sensors give some indication if the cats are working?
05-21-2014, 11:38 AM
#4
You could get hooked up with a VAGCOM and see what exactly is going on with the O2 sensors.
05-21-2014, 07:08 PM
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I have a vag com and have been trying to figure out how to use it. I think the 02 sensors and cats are working fine. The front o2 sensors fluctuate while the rears stay relatively constant(when rpms held constant). Also the rear of the cats are much hotter than the front. I think I may have narrowed it down to the egr valve; it didnt actuate when put under vacuum. Luckily I had a spare egr and put that one in, so ill see tomorrow if that made a difference. If that doesnt fix it im stumped. Ive checked the cats, 02 sensors, water temp sensor, the fuel trim etc, everything seems to be fine. I do however have a slow water leak which I cant seem to pinpoint, all I know for sure is it isnt ending up in the oil.
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