Is it possible to pass an OBDII emissions test with a CE light on? I've had one place tell me that as long as the engine is running clean, it can pass and I've had another place say that ANY CE light will cause a car to fail. I have 3 codes on my 98 328i right now: an 0150 "O2 Sensor Circuit, Bank2-Sensor1 Malfunction", a 1519 "VANOS Faulty Reference Value Intake", and a 1525 "Intake VANOS Solenoid Electrical Fault". I've ordered a new O2 sensor already and I plan on cleaning up the VANOS plunger to see if that will "unstick" the VANOS solenoid. As for the faulty reference code, I have no clue what that is, but I'm hoping that either cleaning the VANOS plunger or replacing the VANOS solenoid (if need be) will clear that code. My question is, if I replace the O2 sensor and then then unplug the battery overnight, will that clear the 02 sensor code, allowing me to pass emissions or do I have to clear everything before I can pass (and finally register my car)?

Thanks,
Pete

Won't pass with a check engine light. You can always reset the check engine light and try and pass it before it comes back on

From the Clean Air Force (http://www.cleanairforce.com/obd.htm) Web site:

If the "Check Engine" or "Service Engine Soon" light is on, a vehicle WILL NOT pass the inspection. This is an indication of an emission control system problem.

I am in Duluth area. If you want, I can try o reset it and then you can try. Cannot assure you it will pass.

After you reset it the car has to be driven for a while in order to be in "ready state" for emissions testing. If not, the Emissions testing computer will not even read anything and they will tell you to go drive for about 50 miles and come back to test again. Oh the joys of OBD II :rolleyes :lol :stickoutt

Thanks for all of the help! I'm going to try to replace the o2 sensor tonight and then clear the codes and go retest next week sometime. Thanks!

Pete