I reset my 170-173 codes yesterday after cleaning my Mass Air Flow Sensor (MAF). I know I need to drive it a certain number of miles, with a certain number of engine starts before I can take the car for an emissions inspection.

I believe the car must be driven 100 miles (+/-). Is this true, and are there a certain number of engine starts required before the code memory clears?

(My state emmission inspection will not pass if there are any codes in memory, even if the problem has been corrected.)

I followed this procedure to reset mine. I don't know if it is correct for your car but it worked on my E430.

http://www.peachparts.com/shopforum/...78&postcount=2

The scanner I have (Equus 3130) states to check the car's manufacturer's shop manual for drive cycle info.

The MB dealer has told me to drive two stints of 50 miles. But I want to know how many times I have to start from cold, if any.

Erasing DTC's causes a computer reset. The computer needs to readapt or you will get a not ready error at the smog check station. I had this happen when I cleared a pending code just prior to going in for the smog check.

There are lots of opinions on what's required. I have read that a single drive cycle including starting the engine, driving until the coolant temp reaches >70 degrees C and then turning off the engine is adequate.

To be sure since I didn't want to have to make a third trip. I drove the car for 2 days making approximately 3 individual trips per day reaching operating temp each time. Total distance was 60 mi. That worked although I'm sure something less might have been okay too.

I was rejected at NJ DMV, because the driving cycle was not completed. The problem was that prior to appearance I was trying to delete with OBD2 tester code PO700, which is for transmission problem, but not emission control. They told me to drive 200 miles and come back. Since then I drove 180 miles and OBD2 tester is still saying that the driving cycle is not completed. I positive that this will be the response of the DMV computer too. I know that the cycle is about 100 miles. any idea?

Start of with a cold engine , turn ign for 30 sec
Start engine let it idle for 2.5 min
2 light acceleration to 35kmph
2 medium acceleration 45 kmph
2 hard acceleration to 55 kmph
5 min at 100kmph
5 min at 90 kmph
return to shop and let idle for 10 min
Please note you want your tank between a quarter and three quarter.

well it looks that cycle went complete, but PO170 code appeared in OBD2 scanner. surprisingly the check engine light is off. OBD2 shows emission control failed.