Fathead

Three questions below. But first, here's the background:

1998 E320 w/ 65,000 miles. CE light illuminated with error codes P0107 & P0173. Started with a new gas cap. No help.

Went to an independent MB-German car mechanic who, over the course of a couple of visits, gave it a carbon blaster induction treatment, 4 new O2 sensors and a MAF sensor. The acceleration was greatly improved; it's a rocket. The idle is steady, no problems. The car appears to function normally.

But the CE light continues to illuminate with error codes P0170 & P0173.

The mechanic has one of the hand held computers that plugs into the port under the hood. I watched as he ran a full diagnostic check (the guy is good. His shop is filled with MB & assorted exotic sports cars).

That said, here's the questions:

Would ONLY the MB dealer be able to reset the fuel trim adaptations or would my independent be able to do it from the handheld unit ? (did not see the brand; it takes cartridges for each make of car, requires entry of vin #, etc)

Assuming the fuel trim adaptations was reset -- I suspect not because the CE light and error codes become present faster than before the MAF sensor replacement -- and assuming there's no vacuum leak, what could be the source of the error codes?

Lastly, any other recommended course of action?

Thanks in advance for your suggestions. I'm facing deadline for the NJ Clean Air inspection so, again, thanks in advance for your help....

redcoupe

The only way that I know to reset the fuel trim is to use the MB diagnostic tool.
What cool was the scan tool the tech was using, and the shape of it(red ambye, rectagular, etc).

I'll try to remeber to look the code up.

But I think, key word think, the P0173 is a "selfadaptaions at limit, left bank.
But know is the other code a P0170 or P0107. You post two different codes.
Because if its P0170 it's another selfadaptaions at limit, left bank.
Which if you get both then it is a mass air flow sensor, most of the time.
But you can also have a vacuum leak to.
Check the vacuum line on the front and back of the intake.

Let us know.

Brian

Fathead

The codes = p0170 and p0173 = are defined as a fuel trim error bank 1 AND bank 2. So yes, I suspect the problem is the MAF was not correclty initialized and the adaptations reset in the computer.


The scan tool was red, retangular, about 1.5 ft by 8 inch. The brand name was printed across the top. It had a mono LCD screen with a thumb wheel upper right hand corner to scroll. Below the thumb wheel were black YES and NO push buttons. I recall the cable came out of the left side of the unit.

The scanner was in a hardcase with about a dozen 2" by 4" cartridge blocks labled for various automobile models. The cartidges plugged into a port, I believe, on the right side of the unit.

redcoupe

Yes that's a snap-on scanner.
A very good scanner to but not MB tool, you can't do as much with the snap-on scanner as your dealer can do. It can only read and erase codes, and look at all you sensor, but not program.

Fathead

Upon further review, yes, that's it. Snap On.

Okay, sounds like I must take it to the dealer for a reset.

Assuming that's the problem, is the dealer going to break my bank? I live in northern NJ.

Thanks for all your help....

redcoupe

It just depends on how much they charge per hour and how much they want to do it.

Brian

Fathead

Thanks, Brian....