Could you help me understand something concerning the fuel pump in my '05 C230K that I just had replaced at the dealership?
The receipt I received for the work says they put in a new fuel pump and "sending unit" as a "matched pair". The pump was $275
and the sending unit was $335. After they put in the new parts, the pump did not work, so they took it out and tested it and found it
had an internal short. OK. They ONLY replaced the pump (at their cost of course), used the SAME "sending unit", and re-did the whole job.

My question is this: If the pump and the sending unit are "matching" parts, why didn't they have to replace the sending unit the second time around as well as the defective pump? And, why do you need a "sending unit" when you replace a dead pump? Doesn't the sending unit just tell the fuel gauge how much fuel is in the tank? Why wouldn't that part be acceptable to use with the new pump, since it costs even more than the pump to replace? Did my dealer pull a fast one here? Or do these things have to be replaced together even though one of them is not really defective?

Thanks for your help.

MrCoyote

 

Any TECH out there???

Please respond.

 

Hellooooooooooooooooo????????????

[:@]

 

most likely what happened is, the intial repair, the wrong fuel pump was installed so they told you that there was a problem with it but there really wasnt one. ive seen several times where that has happened at the dealer before. there is a differnce in the electrical end of the fuel measurement and how it reads. thats probably what happened

 

my question: i have a 1999 c280 with over 100,000 miles. WhenIshift my gearsI can hear the changes.Andhow often shouldthe tranmission fluids need changes.

 

60K is a about right. you should do it soon.

 

Yes, MB transmissions are not "lifetime" and "sealed" as some would have you believe.
The fluid needs to be changed along with the filter. Don't wait. These transmissions are expensive.
Any good independent MB shop can do it for you.

 

My 2 cents even though I am not a mb tech, but I graduated from Va Tech.
If I had to guess, they were probably just covering their bottom.
If they diagnose a problem, it is still only an educated guess as to what is wrong with the car.
If they say only that you need a fuel pump and replace only the pump, but find a problem after putting it all back together with the sender, then they are on the hook for the sender also. But if they sell you both then the likely hood of them fixing the single problem by replacing 2 parts will be greater, this in addition to having more money in their pocket.