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Drive Cycle for Emission test help

45071 Views 16 Replies 6 Participants Last post by  Noodles
So I replaced the MAF on the 01 ML430, and have to get ready for the Smog test here in Ca.
Running it through the code reader, in the I/M readiness, 3 are still not ready yet: EVAP, Sec Air and EGR Sys. If more than one is not ready it wont pass. This is my second week driving it to work and back, its 16+ Mile commute and 20-60min drive.
Can anyone provide any advice on having the EVAP, Sec Air and EGR Sys sensors set?


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actually that seems to have all 3 I codes, just readiness

lets see if it works
Ive done my "normal routine" on getting cars ready, but this one is just taking too long.
My Same route to work takes from 20-60 minutes depending on time and day, and I have taken it other places too, in town, and long drives, so its been pretty mixed.
We'll see how it goes

changed MAF sensor
ive tried and have not set yet
will try more carefully this weekend
just need one more to get set, since it seems I can pass with 2
I was told on a California specific forum, not car related, that it was 2....

anyways its pointless, since I am having trouble setting either one, its been a month of me driving it and doing the drive cycles.
any other ideas I can try?

Please, update your profile with vehicle and location info.

In Texas 96-02 pass with two monitors not ready. '03 up only one.

If you have means to look at live data stream check STFT (Short Term Fuel Trim) and LTFT (Long Term Fuel Trim) values. LTFT needs to be less then 15%, STFT needs to hover +-3%. When monitors take that long to complete there is usually fault code just to pop up.

You have never fully answered question why computer was reset in the first place and what were the codes prior.
MAF was replaced, why? it was bad, no more CE light after the MAF was replaced, had to reset when the MAF was replaced to clear the old CE light. I would reset the CE light before and it would come back either pending or immediately with the old MAF.
It has been running fine after I replaced the MAF, about 400 miles on it, no pending codes with my reader, running better than before actually. I dont have any live data stream capability.

Like I said in it as an 01 ML430,

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