W203 Gearbox problem

[RSTurbo50]

I have a 2006 Mercedes C220 CDi Sport Auto. The car has 111500 miles and I purchased it two weeks ago from a garage. Today after driving to my mums, the car was warmed up and I put my foot down on a dual carriageway, first time Iv really had chance to do this. The car picked up well and it was only when I approached some traffic lights I noticed a fault.
As I pulled away from the lights from a standing start, it felt like the car was stuck in 3rd gear and it wouldnt change up or down. I also tried to press the Sport button but it remained in comfort and wouldnt switch between the two modes. I got to my mums, switched it all off and then restarted it 5 mins later. I took the car for a drive and all was well once more.
Now I have a warranty with the car and will be speaking to them on Monday.
Is this a common fault and has anyone any idea of what it maybe and would it be costly to fix?
Also, Iv noticed that when pulling away from a standing start, it feels like you are always starting off in 2nd gear but I was thinking this was normal as its in comfort mode?
Really concerned as I have only had the car two weeks and so far I have loved it. Taking the family away on holiday next weekend and I am worried that all is not well.

Any advice?

 

[panason1c]

Probably a speed sensor fault but codes will need to be read to confirm, or otherwise...

 

[mersum1es]

If box is in a limp mode, only 2nd and reverse gear are working. If you were in engine limp mode, car may not want to change especially if it's MAF related. Comfort mode is starting with 2nd, but if you use kickdown it should drop to 1st. However, there should be faults stored, codes should be read with Star.

Box faults may be caused by oil leak from ecu plug (check the TCU too, capillarity draws it up!), very common and it's giving very different variety of faults. Also oil level of the box should be checked, and take care that oils are changed 40-60k interval.

 

[RSTurbo50]

Thanks for the replies. I am hoping that the warranty I have will cover any fault that is diagnosed. If not, are these sorts of problems expensive to put right?

Just driven the car again and its been fine since, only that one time when I put my foot down and let the revs build..

 

[panason1c]

Warranty should cover the fault, the possible speed sensor fault that I mentioned is usually an intermittent occurance ......It would be useful for you to have the codes read.

 

[RSTurbo50]

ok cheers ill contact the warranty company on Monday. Is the car ok to drive in the meantime?

 

[E270 Owner]

Have the fluid level checked and the condition of the ATF

 

[240-singh]

Sounds identical to the problem I had on my wife's car. Used to get into limp mode on occasions, then a week or so later was permanently in limp mode with engine light on. Had it on star and was indeed a speed sensor on the conductor plate under the gear box that was gone. Price of part around £200 + labour. Now all sorted. Runs better as they also changed transmission oil and filter which is worth doing at same time.