I am happy to report that the $127 MAF sensor insert from germanstar.net has cured my P0170 CEL problem. To my pleasant surprise, in addition to the elimination of the annoying CEL, the car now has MORE POWER, it shifts smoother, and up-shifts quicker than with the old sensor. With the original sensor 0-60 mph took about 12-14 seconds. Now it is 8-9 seconds!. (This with transmission in regular "drive" mode", both cases). After resetting the old sensor (battery disconnect) the CEL would re-appear within a day or two. I have been CEL-less for over a week with the new insert. Too soon to determine effect on gas mileage
I bought the car (1997 E320 sedan, 70k miles) used in 2004, and the CEL appeared soon after the purchase. For a variety of reasons (expensive MAF, not certain the MAF was the cause, car ran "good-enough", the CEL tripped only when coming to a stop after driving at freeway speed - a transitory problem, good mileage 20-24 mpg) I resisted buying the complete MAF unit. Even $270 for the MAF assembly seemed a poor bet, not knowing for sure that the MAF was the true culprit. I scoured this and other forums looking for knowledge and cheap fixes. Searching for vacuum leaks, cleaning the sensor with MAF cleaner, blocking the charcoal canister (virtual vacuum leak), new air filter, plugs, wires, etc. Nothing worked. (But thanks to the posters for the advice nonetheless -- educational!)
It was just a few weeks ago that I discovered (I think in this forum) the availability of the MAF insert from germanstar.net. $127 was a relatively attractive bet. It has paid off in spades! Here's a big THANK-YOU to the poster steering me to germanstar, and to all others posting on this topic
That at times a new maf will even after running the adapt program,and clearing the codes,at times throw a code ,just clear and drive usually does the trick.If after installing a new maf or insert and a cleared code comes back on again even after the second reset and it is p0170 only,look for a leak in the intake system,if you did not get the air tube on properly or it is crimped to tight around the clamp and such around the area exiting the maf,you can get the p0170.
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