GrimmJeeper
NAXJA Forum User
- Location
- Gardena, CA
well, i failed smog today. it SUCKS. i dont have a scanner so here are my numbers.
at 15mph:
RPM: 1674 | CO2%: 14.9 | O2%: 0.0 | HC (max/measured): 89/33 | CO (max/measured): 0.66/0.02 | NO (max/measured): 517/672 |
at 25mph:
RPM: 1647 | CO2%: 14.9 | O2%: 0.0 | HC (max/measured): 54/30 | CO (max/measured): 0.80/0.02 | NO (max/measured): 770/608 |
so as you can see i failed the 15mph NOx. the smog guy said for the past year or so they have been getting 10 or so jeeps a month, 91-96 4.0s, that just wont pass. even after changing out every sensor, the cat, and doing full tuneups.. he had me go talk to a shop down the street, a CA gold shield smog repair station, and i spent a good hour discussing this with him. he said they were comepletely baffled. he thinks the main problem is that the computer controls the timing on the motor, and since the smog regulations changed, the old computer timing at low RPM is not working at its best efficiency, because it wasnt required before now.
anyways, before i throw ANY money that i dont have into this thing, does anyone have any ideas? Andy says colder heat range plugs, my boss says change the cat (mine has +/- 50k on it) the smog guy says the computer is fuXXed and its the factory's responsibility to put out a recal to re-flash the computer, i just dont know where to start.
i WILL figure this out (i hope) and keep this thread updated because it sounds like a bunch of us are going to be running into this problem sometime in the near future.
thanks alot CARB!:smsoap:
at 15mph:
RPM: 1674 | CO2%: 14.9 | O2%: 0.0 | HC (max/measured): 89/33 | CO (max/measured): 0.66/0.02 | NO (max/measured): 517/672 |
at 25mph:
RPM: 1647 | CO2%: 14.9 | O2%: 0.0 | HC (max/measured): 54/30 | CO (max/measured): 0.80/0.02 | NO (max/measured): 770/608 |
so as you can see i failed the 15mph NOx. the smog guy said for the past year or so they have been getting 10 or so jeeps a month, 91-96 4.0s, that just wont pass. even after changing out every sensor, the cat, and doing full tuneups.. he had me go talk to a shop down the street, a CA gold shield smog repair station, and i spent a good hour discussing this with him. he said they were comepletely baffled. he thinks the main problem is that the computer controls the timing on the motor, and since the smog regulations changed, the old computer timing at low RPM is not working at its best efficiency, because it wasnt required before now.
anyways, before i throw ANY money that i dont have into this thing, does anyone have any ideas? Andy says colder heat range plugs, my boss says change the cat (mine has +/- 50k on it) the smog guy says the computer is fuXXed and its the factory's responsibility to put out a recal to re-flash the computer, i just dont know where to start.
i WILL figure this out (i hope) and keep this thread updated because it sounds like a bunch of us are going to be running into this problem sometime in the near future.
thanks alot CARB!:smsoap:
