Fuel Adaptation Reset

[dyazdani]

I have a '97 MB C230, the CE light came on with the code p0170. After extensive searching, I decided to replace the MAF. The CE light went away for a bit, but came back on with p0170 and p0300, 0301, 0302 (multiple misfires).

I've read that after you replace the MAF, sometimes it is required for a mechanic to reset the fuel adaptation, otherwise the car will run rich. It seems that my car may have that symptom.

What do you guys think? Is there a way to reset the adaptation myself?

[audiophile]

same code came up in my car but haven't switched the maf. where did you find yours at

[dyazdani]

I found one off a misdiagnosed car for $20 on eBay.

[jnolte]

Its not smart to buy a MAF sensor used, MB MAF sensors are very fragile and can be messed up easily. Its best to buy new, www.importec.com or www.thebenzbin.com has them for around 250

[moebiusgold]

That sounds too similar to my experience. Local benz dealer sold me an "unused return". In my experience it went way lean and that caused the misfires. I think that you wasted 20$. Put a scanner on it and find out the LBS per Min. and where the long and short term fuel trims are. That tells the truth. P0170 wasn't triggered untile my long term went over 35%. I went and returned mine the next day and got a box with the seals intact and everything worked fine after about 50 miles of driving.

[dyazdani]

If my MAF was bad, then it doesn't hurt to put in another "bad" one. I took a chance on a $20 fix to see if it made a difference.

What is a normal value for the lb.min? I guess it changes with speed/rpm.

[moebiusgold]

My C36 idles at about .73 Lbs/Min when hot with a long term fuel trim of -1.3%

[J Irwan]

Originally posted by dyazdani
I found one off a misdiagnosed car for $20 on eBay.


Last time the dealer replaced my MAF the MSRP is $550 if I am not mistaken, and luckily warranty covered it..

Otherwise I'll be really pissed since the best price for a brand new MAF/MAS is somewhere around $260ish

And you got it for$20 of ebay, sounds too good to be true..
maybe the seller had you fooled.

it is not easy to diagnose bad/good MAS/MAF without measuring it.. let alone just seeing the pic..

Let this be lesson learned.
Like the other has mentioned never buy used MAS/MAF --> you'll end up buying junk.. :)



Regardz,

[dyazdani]

I don't mind spending $300 on a new MAF if I know that is the problem. I want to eliminate other possiblilities before I throw money at parts.

Will reading the actual airflow tell me if the MAF is actually bad? Is there any other test I can do? How about a fuse, is there a fuse that may have interupted its power supply?

Thanks!