August 18, 200718 yr I just failed my emissions testing in a 1996 Cutlass. This was caused by a replaced battery that same morning. I was told I need to find out what the drive cycle is so it can reset the monitors to "ready". Does anyone know what the drive cycle is?
August 22, 200718 yr No, the monitors are systems within the ECM that "learn" what the proper operating parameters are for that particular system, such as you have an EGR monitor, a Misfire monitor and such. Each vechile is different, but from what I know about drive cycles, it typically involves driving a vehicle a x speed for y amount of time and then having the monitors checked using an OBD-II scanner to see which ones have reset and the like.
August 23, 200718 yr No, the monitors are systems within the ECM that "learn" what the proper operating parameters are for that particular system, such as you have an EGR monitor, a Misfire monitor and such. Each vechile is different, but from what I know about drive cycles, it typically involves driving a vehicle a x speed for y amount of time and then having the monitors checked using an OBD-II scanner to see which ones have reset and the like. So you have to drive it to reset it?
August 23, 200718 yr Correct, that's what a "drive cycle" is, you have to drive the vehicle a x mph for y time for the emissions monitors to "cycle" themselves and become "ready". If any of those monitors aren't in a "ready" state, then you'll fail your state's emissions check. And the things that can reset those are loosing electrical power at any point in time, removing the computer from the vehicle, or erasing the check engine light codes. Once any of those are done, then you're going to have to perform a drive cycle on the car in order to get those monitors back to their normal "ready" state.
August 23, 200718 yr WTF? Don;t you just LOVE modern cars and their reliable simplicity! Sorry I can't help, I've never even heard of this silliness.
August 23, 200718 yr ^^^ trueness. My mom's intrigue failed automatically because it was throwing an SES engine code. The didn't even see if ti related to the emissions, to most state emissions facitilities these days a SES light is an auto fail regardless of what it means. Turns out the intrigue was throwing a MAF air sensore malfunction code because the air box had gotten clogged with crap. I used a friends scanner to figure out eh code then pulled apart the airbox to take a loog arouund and it was loaded with road junk. Cleaned it out, reset the PCM and drove it around for a few days. The SES stayed off, I broguth it back to the test site and it passed with flying colors.
August 24, 200718 yr Yeah, I believe that within every state with stricter emissions requirements, if he SES, or CEL is on, then its an automatic fail, even if the code is for something nonchalant, it will automatically fail, and until the check engine light is off and the emissions system monitors are all in their "ready" state, the vehicle will fail emissions requirements.
August 24, 200718 yr Last time I checked, MAF sensors and emissions didn't exist in 1969, or 1959 or 1949....
August 24, 200718 yr Correct, that's what a "drive cycle" is, you have to drive the vehicle a x mph for y time for the emissions monitors to "cycle" themselves and become "ready". If any of those monitors aren't in a "ready" state, then you'll fail your state's emissions check. And the things that can reset those are loosing electrical power at any point in time, removing the computer from the vehicle, or erasing the check engine light codes. Once any of those are done, then you're going to have to perform a drive cycle on the car in order to get those monitors back to their normal "ready" state. Ah, I learned something new today....
August 27, 200718 yr Glad that I could help. Just remember I'm your friendly parts guy/technician (since well my "normal" job is a parts guy, and I service vehicles on the side).
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