How long does it take for the ECU to log in EMISSIONS info?

[im2bad4ya]

I got my car with expired inspection, and since replacing the battery, I've driven about 120 miles. I've been to the inspection place 3 times now and all 3 times it's failed because the OBDII for the emissions system wasn't "ready". I've looked in the owner's manual but couldn't find anything. Does anyone know how many miles I have to drive for the emissions system to be ready??

 

[SeR_Cyclops]

I dont know what you are talking about, the emission system is always working so why would it not be "Ready"?

 

[njaremka]

you need to run through roughly half a tank of gas, and run the car through at least two cold start / warm up cycles. it helps to run the car for 10-15 minutes at highway cruise speed each cycle, too. (do not exceed 65mph)

helps to have your own OBD scanner that will tell you what ECU cycles are pending, also.

 

[im2bad4ya]

The OBD logs information related to the car right? Reads engine misfire, fuel systems, catalytic converters, evaporative system, EGR system and oxygen sensors among other things. It's called "OBD/Readiness Driving". Most of these systems are read every time you start the car, but evaporative system, catalytic converter and oxygen sensors are a culmination of the times you drive and stored on the ECU memory. At NJ inspection they hook up their computer to the OBDII port to get the readings of the emissions system. So the first two times I went to inspection, the three aforementioned systems had a "NOT READY" status causing me to fail. 3rd time I went, evaporative system was "READY" (and I had 120 miles on the car since replacing the battery, ergo restting the ECU) but catalytic converter and oxygen sensors were still "NOT READY" Basically I have to drive a certain amount of miles for the car to log those specs to get a "READY" status and ultimately a PASS or FAIL. The guys at inspection recommended 100 miles, but obviously only 1 of 3 were ready at that point.

So was seeing if anyone knows what I'm talkin about and the magic number of miles for those systems to be 'ready'

 

[njaremka]

read my post above. i can reset my ECU, and have all codes ready for test within a couple days. note: some codes will not show "ready" if the fuel level in the tank is not within a certain range. that's why i suggest running through about a half tank.

there is no "magic miles" number for OBD readiness, because there are cycles that need to be run. if you drive a certain number of miles, but never meet the criteria for cycles, its not ready.

do yourself a favor, and pick up a cheap scanner from walmart that can show you when the cycles are ready. then, only schedule your test after they are good.