I have a 99 ML320 that the dealer says needs an O2 sensor and a mass air sensor. The problem has existed for over six months but they claim that they have only just found the cause. The "service engine" light has been on the whole time.

They claim that it is off warranty now and the estimate is for $1200 cdn.

Does anyone have any info on:

Service bulletins
Secret Warranties
Past histories on this problem. Is it common ?

Thanks in advance for your help.

I don't have a clue to fixing your problem, but this is addressed to the MBUSA people that lurk on this list. I'm betting you can make this guy happy real quick and keep this from getting out of hand. Of course, you could play like GM and figure you don't need to keep people happy with the impressive numbers you've been posting on sales.

So why not get it right the first time and calibrate the dealer while you're at it? I'd like to think you've got a better operation than GM or Toyota.

someguyfromMaryland

Hi, I feel bad for you my friend. The way to go with this problem is to tuff it out for a short time. Get all of you prior paper work showing the number of times you've tried to get repairs under warranty and any other pertinant items involving this issue. Next go to the service manager for satisfaction. Do not be arrogant or hostile as this will slow things down ( even though you have a right to) If no help, go up the line to the owner of the dealership. If you get no help from the dealer your next stop is the area MB rep. I had a similiar problem with another car. I followed this procedure and ended up with my entire repair bill ($ 3000) being handled by the dealer. DO NOT SPEND YOUR MONEY UNTIL THE LAST RESORT) you probably won't get it back even if they say it's their fault. If you want to cut this short, go directly to the area MB rep. You paid to much money for this type of crap! It is obvious that your problem should have been determined and repaired by the dealer on the first visit. Good luck and let us know how you make out!!

Try here for the mass air sensor! Part number is 112-094-00-48. list is $ 275 US.
The O2 sensor part number is 000-540-81-17. list is $ 115 US

__________________
MERCEDES Benz Master Guild Technician (6 TIMES)
ASE Master Technician
Mercedes Benz Star Technician (2 times)
44 years foreign automotive repair
27 Years M.B. Shop foreman (dealer)
MB technical information Specialist (15 years)
190E 2.3 16V ITS SCCA race car (sold)
1986 190E 2.3 16V 2.5 (sold)
Retired Moderator

Is the mass air flow sensor part of the emission system.and if so would it not be part of the 5year warranty on emmission parts?

In 1996 the US government extended the EMISSION warranty to 8 years or 80,000 miles, the bad news is that very few parts are now covered. The fuel computer & catalyst are 2 of the few number. ALMOST no sensors are covered!

__________________
MERCEDES Benz Master Guild Technician (6 TIMES)
ASE Master Technician
Mercedes Benz Star Technician (2 times)
44 years foreign automotive repair
27 Years M.B. Shop foreman (dealer)
MB technical information Specialist (15 years)
190E 2.3 16V ITS SCCA race car (sold)
1986 190E 2.3 16V 2.5 (sold)
Retired Moderator

If 3 times for same problem unfixed....Can you say "L-E-M-O-N-aid" boys & girls? chk. your states lemon-law, if you have one. Let's see......O2 sensor...hmmmm.....that'll be about $27K, Mr. Daimler.

Before anyone thinks about any lemon(s), most states allow for repeat problems durning the first year or 2 years of ownership ONLY to the original owner!!

__________________
MERCEDES Benz Master Guild Technician (6 TIMES)
ASE Master Technician
Mercedes Benz Star Technician (2 times)
44 years foreign automotive repair
27 Years M.B. Shop foreman (dealer)
MB technical information Specialist (15 years)
190E 2.3 16V ITS SCCA race car (sold)
1986 190E 2.3 16V 2.5 (sold)
Retired Moderator

My brother has an E320 and the Mass flow sensor just went bad. The car is only five years old and not a whole lot of mileage.

It sounds like this part goes bad way too often. Was there a factory recall on this part??

__________________
Patrick Leber
'84 190E 2.3
'83 Porsche 944 (track car)
'84 Porsche 944 (parts car)
85.5 Porsche 944 (sled)

The one in my 1997 E320 went bad a few month ago at 57k miles. Cost was around $800 to replace. MB really should pick this up.

Bo

Which vendor manufactures the MAS?

It seems with the mass globalization of products these days, there is no such thing as a german car anymore. I am wondering who Benz vends this part manufacturing out to.

__________________
Patrick Leber
'84 190E 2.3
'83 Porsche 944 (track car)
'84 Porsche 944 (parts car)
85.5 Porsche 944 (sled)

I can sympathize since I just got word that my wife's 1994 E320 wagon needs...a new mass air sensor! However the cost will be $690 plus tax (Cdn). This is from the MB Canada shop (all of the ones in Toronto are). The mass air sensor is $415 and the rest is labour including diagnosis.

So your quote seems a bit high.

I also asked the service rep to see if he could do something better than that. Who knows, don't as, don't get. I'm not in as good shape as you since I'm the 3rd owner and it's a '94 and it has 110,000 km. So you should get it fixed on MB's buck. Really. If it were more money I would even suggest it's worth a small claims action (yep, I'm a lawyer).

Good luck.

Bosch would be that vender on the air mass sensor!! VERY high failure rate!!! However MB must take some of the blame as they installed this sensor directly above the EXHAUST manifold.

__________________
MERCEDES Benz Master Guild Technician (6 TIMES)
ASE Master Technician
Mercedes Benz Star Technician (2 times)
44 years foreign automotive repair
27 Years M.B. Shop foreman (dealer)
MB technical information Specialist (15 years)
190E 2.3 16V ITS SCCA race car (sold)
1986 190E 2.3 16V 2.5 (sold)
Retired Moderator

Does that mean the replacement will also fail soon due to the heat?

Or Does MB make some modification when installing the new sensor?

Bo

Since they will be putting it in today, should I insist that they put in some sort of heat shielding? If so, I have to call MB ASAP.

BTW is the part from Bosch cheaper by much?