07 3500: Kick-down Switch Useless or Other Issues?

After lurking on the forum for a while, I went out and bought a higher mileage 2007 Sprinter 3500 170": around 180k on the ticker.

The kick-down switch (the click at the bottom of the throttle travel) does not appear to do anything. Usually, on MB cars, the kick-down results in a downshift and max power being applied, but on my big Sprinter, nothing happens; no downshift, nothing.

Seems unusual, has anyone else had this happen?

I've tried to roll my own kick down by keeping it floored and downshifting, to see if I just have too high expectations for the power of this truck, but to no avail. The downshift happens, but no additional oomph comes. It just hovers at the higher RPM.

The mothership can't seem to hold 65 mph up a very modest incline on the highway which puzzles me, because I expected a wash of turbo-torque to pull it along at those speeds.

All this is with only the shelving which came with it inside. I am thinking cleaning the EGR valve / cooler will be everyone's natural response to this problem.

Yeah, I'd suspect the EGR valve, cooler and temp sensor are fouled, but that's just because I equate all "no guts" postings in the NCV3 section with EGR system fouling/failure.


Still, in an effort to get over my prejudice, did you get service records with the van?

Oh, I'm not sure that my 2500 goes down to 4th if I floor it on the freeway doing 60. It might, but I've never done it. I seem to remember, going up an incline over 50 mph, it does, but I don't recall specifically.

-Jon

The only time my van will not kick down , is when I'm above 74 mph. It's definitely in a reduced power mode if you can't get above 65 and empty. Check your charge air system for oil leaks, this means you have an air leak. Then check both turbo regulator and the swirl valve motor, these will both work intermittently without showing a CEL. Only when they completely fail do they. Thro a code. I would have a sds system test performed on a used van.....preferably beforehand. When my TCM is in the learning adaptive process my van rips from 65-86 mph

1. no service records, and stupidly, I didn't even run a carfax [facepalm]
2. I'll have to get that done at some point, I am not looking for V-10 pull or anything, I would like to maintain speed up a grade.

It also topped out at about 74mph on the flat. I was reading about how some people have limiters on them, mine was a tool company van, is it possible it is limited? Doesn't seem likely.

obso1377,
Something may be wrong, and then again nothing may be wrong.
There is no "kick down" switch on a Sprinter that I know of.
So, as a test, and as a better way to get good fuel mileage and be able
to maintain your speed up grades, why not simply tap the shifter to the left
(toward the steering column on LH Drive NAFTA Sprinters) to drop the transmission
down to the next lower gear.
Understand, that your Sprinter is in OVERDRIVE (0.83:1) when in 5th gear.
See what speed and RPMs you get in 4th gear.
Sprinter vans are not light, and trying to lug up hills in Overdrive makes no
sense! Manually downshifting takes care of this completely!
The TCM and ECM will prevent you from manually downshifting into a gear that will over rev
your engine.
You will be able to run 65 MPH @ approx. 3200 RPMs all day if need be, in 4th gear (1:1 ratio).
In order to have good power for pulling uphill grades, you need to get the engine
RPMs up into the 2800-3600 range where your Sprinter V6 makes it's maximum
horsepower.
If you don't like running seemingly very normal RPMs, be sure to downshift well
in advance of uphill grades to get the RPM > 2400 (max. torque) for sure.
Also, what tire size are you running...... tall tires can affect how the transmission
downshifts (or not).
What trans fluid are you running? When was it last changed and what fluid did they
refill it with.
Check your plastic transmission electrical connector on the lower RH front of the
trans. If you see fluid inside you need to change out the connector and it's O'ring
seals.
A max of 74 mph does not sound right.
Might want to get it to a good Mercedes Authorized Sprinter dealer with the
MB SDS (Star Diagnosis System) scanning tool.
They can tell you if there are any DTC codes, and if the top speed governor
has been reset below the normal 82 mph.
They can also have a look at the Transmission Control Module (TCM) and check
if everything is within normal limits in the trans control system.
This would be far better than a CARFAX!
Hope this helps,
Roger

74 mph is the speed of the optional speed governor (Dodge option code XFS - not sure of the MB code).

If you post the VIN, someone can pull the MB data card from epc.startekinfo.com.


The data card will show if the van was built - if it left the factory in Germany - with the 74 mph speed limiter.




Source: https://sprinter-source.com/forums/showthread.php?t=1279

-Jon

1. the "kick down" switch is there, you can feel it when the accelerator is depressed till it makes contact with the floor, then slightly increase pressure, you should hear and feel a click which is the switch being triggered. MB adaptive accelerator maps adjust how much throttle activation you get for a given level of accelerator pedal travel, on our old E320 if my mom drove it for a few months, it would be super gentle with acceleration, the only way to tell it you wanted moar power sooner was to click the kick down switch repeatedly, and after a few pull-aways, the adaptive throttle would get more aggressive so you didn't have to hit the kickdown. I don't really plan on driving the sprinter really aggressively at all, I'm trying to feel out what needs to be repaired / replaced.

2. As I type, the sprinter is at MB service getting the Service B stuff done, plus I told them to do a transmission service and drain / refill the rear diff. This is a bunch of routine maintenance stuff which might address some of that sluggishness, or maybe not. I also assume that the transmission service is so expensive because they test the TCM.

3. I would appreciate it if someone could get me the build sheet on my sprinter. I don't think I'd probably get a ecu reflash just to get rid of a limiter, but it would be interesting to know if it has one.
WD0pf445475180761

Roger - I'm fine with getting out of O/D to get up steep inclines, my only concern was that these were very pathetic little rises in the highway, almost not justified to call them hills. My sprinter was maybe carrying 700 lbs of payload [empty contractor shelves and a 250cc dirtbike], hardly approaching its supposed limits, and it seemed to struggle right where I expected some TD power. The wheels are the stock 16's, I'm not sure of the size but I'm assuming they are no different than factory.

Thanks for all the feedback, I'm going over to the MB dealer to pick it up now. We shall see if it is improved at all.

Didn't come from the factory with the speed limiter option, as far as I can tell; I just skimmed it.

If it wasn't built with the speed limiter, it shouldn't be a problem for an MB dealership to restore the original top speed of 82 mph.

I own the Dodge scan tool, StarMOBILE. I am able to reduce my Sprinter's top speed with it. I can not increase it with the StarMOBILE in stand-alone-mode.

In order to restore top speed, I have to "restore" the engine control module's original programming which requires me to subscribe to techauthority.com so my scan tool can download the original programming from Chrysler.

I don't know how an MB dealership would go about restoring the top speed. I can print the instructions that a dodge technician would follow.... every dodge dealership has the tool to do it, whether they know it or not.

-Jon

Well the AC blows strong, and it seems to have a bit more giddyap at lower speeds, but the highway / gutlessness continues. Something I will have to deal with a bit later, I'm off to Utah.

Jon thanks again for the sheet. Quite interesting.

obso1337,
I stand corrected on the "kick down" switch.
Guess in my 160K + miles in Sprinters, I've never pushed the throttle down that far.
My current Sprinter has some sort of switch in the base of the throttle positioner, and it could be a switch to initate
downshifts, but as I said I'm sure I've never needed to push the throttle down that far.
My 2011 170 wb NCV3 3500 auto downshifts very nicely with anything more than about 1/2 throttle in I punch it.
I tried to reach the switch point a couple of times this evening, and the trans auto downshifted well before I got to
the point I could feel the added pedal pressure of the switch.
Anyone got a schematic of the 2010-2012 throttle position sensor and the little switch that's
depressed by the pin on the back of the pedal arm?
If I punched my 2011 in 1st gear, it would be well over redline and into the rev limiter long before I get to the switch
and probably smoke all 4 back tires in the process.
If you don't have enough power and are pushing the pedal to max. (activating the kick down switch, if that's what it really is?)
then you definitely have some engine issues.
Roger

jdcaples said:

Didn't come from the factory with the speed limiter option, as far as I can tell; I just skimmed it.

If it wasn't built with the speed limiter, it shouldn't be a problem for an MB dealership to restore the original top speed of 82 mph.

I own the Dodge scan tool, StarMOBILE. I am able to reduce my Sprinter's top speed with it. I can not increase it with the StarMOBILE in stand-alone-mode.

In order to restore top speed, I have to "restore" the engine control module's original programming which requires me to subscribe to techauthority.com so my scan tool can download the original programming from Chrysler.

I don't know how an MB dealership would go about restoring the top speed. I can print the instructions that a dodge technician would follow.... every dodge dealership has the tool to do it, whether they know it or not.

-Jon

Click to expand...

It is possible that the dealer set the limiter to 74mph to fulfill a fleet order requirement on a lot-stock unit.

well after about 2k miles i think i have a better idea what the issue is. The problem is that the sprinter chokes itself just before 3000 rpm. the cel is for a flap motor in the intake system, the swirl valve, right?

point being that it will chug up to 3k in every gear, but cant move past it. Im going to clean out the egr valve / cooler today to see if that helps anything.