kcscout

I was wondering how long I should expect the Oxygen sensors to last in the W140. I have a 97 S320 with 237K miles. I changed both O2 sensors about 50K miles ago and now I am getting the check engine light with the O2 sensor being the problem. Is this normal. What is the typical life expectancy of an O2 sensor?

oldsinner111

50,000 to 80,000 mile lifespan,buy the best

kcscout

Thanks for the response Oldsinner. I don't feel so bad about having to drop $175 for a pair of sesnors. At least they are fairly simple to change out. Last time I went ahead and got the Bosch sensors. Is that the "Best" or is there another brand that will give me better service life.

eddie a

Are you getting an 02 sensor code? If not read your codes and youll know what the problem is..

oldsinner111

you might be burning a little oil which causes the O2 sensor to get dirty.Chrysler makes and sells a combustion chamber cleaner.I follow directions and see if you sensors last longer.Normal life for good mpg 65,000 to 95,000.Mine has 176000 but I clean my combustiomn chamber twice a year

kcscout

Yea I read the code. My code reader gives me the code description which reads "O2 Sensor Bank 1 Sensor 1". Not sure which sensor that is thought (Front or back).

kcscout

I guess it is possible, but my engine has never shown signs of burning oil before. I only use synthetic oil, I change my oil every 5K miles and I never have to add any oil between changes. I would like to get more information on the combustion chamber treatment though. I plan to keep this car for another 250K miles and I figure I will need that at some point. I will pull one of the O2 sensors to see if there is any oil film on it. Thanks for the suggestion.

oldsinner111

Syn. Oil. Huh my engine hated it,that why I,ve gone to diesel oil 15w 40. Its a old trick for gas engines to last way longer that energy conserving cutting oils./I call these new oils cutting oils,I'm a CNC Lathe and Mill man.
But go with your heart.Some motor oils like super tech Wal Mart brand causes my m104 to lose oil,or it evaporates.
Thats why I stick with Rotella. My new 1/4 mile time 14.570. proves the nitrous gain and orignal horsepower.

kcscout

Dude it sounds like you and me would get along real well. My first MB was the family hand me down 1968 220 D. I know that 4 cly diesel like the back of my hand. My dad was a WW@ Navy diesel mechanic and I remember the day he first saw that 220 D. You would have thought that he found a pot of gold. I was only 10 at the time but he taught me everything about that car. Over the years I have had at least 5 240 D's (the old W123 body) and a couple of 300 SD's (the old W126 body). I switched to the W140 gasoline engine when Diesel hit $4 a gallon. My dad is 87 now and still has a MB Diesel (a 97 E300D). Im not crazy about that air aspirated engine but it just keeps on ticking. I'm also a Power Plant Engineer and we use synthetic oil in all of our heavy gear trains. I promise you that a quality synthetic is far superior to the Rotella 15W40 you are using. The cheap snythetics are garbage. Stick with Mobile, Penzoil, Casteroil, or Quaker State. These synthetics just don't break down and never stop lubricating. You can drain your crank case the the film they leave behind will do a better job of lubricating than a full crank case of regular oil. The worst problem you may have is when switching over from regular to synthetic. The synthetic will remove all the varnish inside your engine which may be plugging up some leaks. Anyway, my engine is smooth as silk and I credit that to the use of quality synthetic oil.

oldsinner111

I 'll stick with 15w40 ,my Dad had over 400,000 miles on a 390 ford,and running when traded.
PS. I will quit helping people as there are two rude person trying to start fights. I encrourage other to report them also.watch out for The E.A. dude

oldsinner111

you dont have a car in you garage

kcscout

Just ignore that crap. This is an open forum which should be for a fun and light exchange of information and experiences. I don't take this too seriously and neither should you. I certainly wont hold you or any of the other novices responsible for inaccurate advice. It's my job to be discriminating in what advice I accept. But back to the oils though, Rotella is great for the diesels but not so good the the high performance gasoline engines. You really need a better lubricating, lighter weight oil to do the job. I swore by Rotella when I was running the diesels but moved on when I switched to gasoline.