Chrasmus

When I tried to accelerate my S350 going onto a highway, the RPMs would not go above approx. 1,200 and my speed only made it to 30-40 mph, even when I floored the gas pedal. I managed to pull over on the side - turned the car off - and everything was back to normal when I restarted it.

The car has 48,000 miles on it, has always been serviced by the dealer (last service three weeks ago), and has never had any problems.

Any info. re. what the problem might be would be greatly appreciated!

Thank you,

Christian

kajtek1

Check Codes.

Carsy

Sounds as if the car went into limp mode then reset.

As kajtek says there should be a code .

mbdiesel12

I have a 2012 E350 BT and had the exact same problem about 3 years ago.


The car acted exactly like yours. I stopped on the side of the road and restarted it. It ran fine after the restart. It's only happened once since I've owned the car.


I took it to the dealer at the time but there were no codes found. Apparently not all limp home problems cause a code. The restart must have rebooted one of the computers and cleared the problem without a code being retained.

Plutoe

The second poster started all this misinformation--with his famous post getting---where is the code and as advised not all issues create faults or codes, simply acquired a spamming post.

The second point, that of limp mode, is misused and I don't think the car was in the classic transmission electrical or mechanical limp mode(no shift issues mentioned)-----for all we know the pedal sensor could be failing and not sending its position to he ECU---or a host of all sorts of issues.

The good news is that the driver was able to restart his car and finish his day

mbdiesel12

I agree that we tend to oversimplify electrical and computer problems. We have a tendency to believe that every situation results in a corresponding self-diagnosing condition. It's never that simple in the software or electronics field. If it were all we would need is an OBD scanner which quite often just diagnoses symptoms that could relate to the actual problem.


I had read about the pedal sensor issue prior to my dealer visit and specifically asked if that could be a problem. The dealers master tech said not on my model and model year. At that point I had no basis to pursue the issue further. It's been 2-3 years without another occurrence.

Chrasmus

Thank you for all the feedback!

I took my car to the dealer today, and they told me that a hose supplying air to the engine had failed - and that they were ordering a new one.

The repair is covered under warranty, and they gave me a loaner to drive until my car is fixed.

Thanks again,

Christian

DubVBenz

Similar problem with my 07 E320 bluetec a few years ago. Although I believe it was actually the ductwork supplying boost, not a hose. Anyways, it had a split in it that would only open up when the the engine was warm and I had just rung it out (as if flooring it from 50-80MPH at full throttle). Took a while to diagnose as it would only happen under that exact scenario and the split was on the bottom-side.

kajtek1

Good that dealers don't employ people like Plutoe.
When code don't always pinpoint the problem, they give you direction.
I had split hose on older diesel as well and code was showing too low boost pressure.
Took some leg work to determinate it was not old wastegate, but split in the intercooler hose.
Interesting that our 2008 Bluetec had couple of splits on the hose, I think due the mechanics kinking the hose during other repairs, but I never had a code.
The area was dirty from oily fumes, but no errors.

pinebaron

Same car, same year. That is interesting; it's happened to me about four times since new. Stopping and restarting cured the problem. Can you please point me to the ductwork you had issues with.

kajtek1

Any leak in intercooler piping will show wet, oily spot around (thanks to engine breath pipe coming at turbo inlet)
If you keep your engine clean, you will spot it right away.
If you keep your engine filthy.... well....

DubVBenz

Will try to find the exact replacement part this weekend when I visit my mechanic. He mentioned the part was so cheap that Mercedes must be aware of its faulty nature.

DubVBenz

The hose that split on my was the ductwork from the turbo to the intercooler. The ductwork from the intercooler back to the engine was also showing fatigue. I replaced both at the same time.

kajtek1

I can only admire your mechanic consideration for "cheap"
The passenger side hose retails about $180 and I doubt the driver side is much cheaper.

pinebaron

I'll take a look today. Thanks.

JJFelock

Now on my third iteration of the same problem for my 2013 S350 Bluetec with 70K miles. In April, the car could not get over 1500 rpm and it took many minutes for it to achieve highway speed. Took it directly to the dealer, they said it was a clogged fuel filter. Problem solved (or so I thought). July, same exact problem occurred again, went to the dealer and they replaced the fuel pump (warranty had just expired, but they covered it). Now here in October, it's doing it again. Happened one day, didn't happen for 2 days, then happened again. The dealer claims there are no fault codes detected and they can neither replicate the issue or deduce the problem. I welcome any and all ideas and suggestions. Thanks.

Time to sell? Too bad, I love the car.

kajtek1

Drive with bluetooth plug constantly on and observe live data on your android.