Hey guys i have a 99 mercedes ml320 and i am getting 2 codes it is po170 po173. Most things i have read is that it is the maf sensor. The local oreillys actually had the part in stock and i got it after almost having a heart attack when i heard the price of $209.00. Anyway i installed it and drove it a good 40 or 50 miles and cel is still on. Now will it go off by it self or is it best to turn it off with my scanner. I know this aint f150 related but the people on the mercedes forum wont reply to me..and i know you guys will help!!THANKS

 

You should have just cleaned it. Disconnect the battery with the lights on for several minutes to reset you computer. If the light comes back on you still have a problem.

 

i would turn it off with a scanner and then disconnect your battery for a lil bit, then see if it comes bak

 

Yep, some makes you have a reset tool to reset a code. You cant just undo the battery to make it go out. I know BMW is that way but not sure about Mercedes. Those expense make really love to suck you wallet dry.

 

Well i turned it off with the scanner and so far after 75 miles its still good no cel. Mercedes is a awesome vehicle but when the sucker needs to have maintance its usually a nightmare. Wife always tells me everytime the hood is raised there goes atleast a grand. Oh well its working for now

 

A CEL generally won't post until a self-test has failed in two consecutive drive cycles in which the selft test has run.

There are exceptions, for example- severe misfires, but mixture-relates faults generally do require the twice-failure.

Steve