Limp mode after kick down

[lt4vette]

I have had a problem for a while with the car (CLK320 cab, MY2000) going in to limp mode after accelerating briskly to overtake for example. I have finally narrowed it down to happening whenever the kickdown button is pushed. This will happen even from a standing start if I push the accelerator hard enough to depress the kickdown button, even though it is obviously not actually kicking down. It does not have to go to high revs - if I do this from standing or low speed, and back of at 2000 rpm the car will then be in limp mode.

I have replaced the MAF sensor with no effect.

Has anyone else had this problem and can give me any clues?

Thanks, Russell

 

[jrggino]

I have a similar issue with my E300td. I noted that if i did a long motorway journey, if i kicked down i had no reponce with the kickdown, the engine would rev, but it had no go. It would drive ok but seemed to lack power , i guess because it would not kick down correctly.
I decided to have the gear box oil changed and filters, which i did, and at the moment touch wood I have not had the problem so far. I am interested in what other drivers report on this .
Gino

 

[lt4vette]

Thanks Gino - that certainly sounds similar. How long has it been OK for? It sounds like it only happened for you when it got hot, whereas mine will do it anytime, but that doesn't mean its not the same cause. Have you had it hot since you did the changes?
Russell

 

[amwebby]

I had the same symptoms but the cause of the fault was the upstream O2 sensor. Like you I thought it was the MAF.

 

[jrggino]

Hi, i noticed it more if i was using motorways doing over 95mph. touch wood its been ok and i am in italy at the moment and its hot, been doing lots of motor way work.
whats the sensors ! not sure what the abrif means sorry lol

 

[amwebby]

Oxygen sensors. There are two, either side of the cat. They feed to information back to the ECU to adjust levels, hence they mess up the mixture, usually under hard acceleration.

 

[jrggino]

Roger thanks for the info. I must understand from this that my diesel pump is electronicaly controled!

 

[lt4vette]

Finally had it diagnosed at MB dealer - DTc said it was the "pedal position sensor". I was a bit sceptical because it didn't seem to fit the symptoms very well, but for a "mere" AUD700 (about UKP300), a new sensor did fix it.

 

[aka$h]

Ive got a similar problem on my E320 cdi, if I kick down from standstill at just past 3000rpm the EL Power Control warngin comes up. The car will continue to drive correctly thereafter and once turned off and on the message is deleted. DAS shows the same fault Pedal Value Sensor.

MB have my car in for warranty repair, so when itsback Ill replace the sensor. The part is around £100 to buy, Ill update on how hard it is to fit. Looks simple, if it doesnt need a laptop to initiate the new unit.

 

[greyboy]

I get the same warning as aka$h when i floor the throttle in my 2001 E320CDi estate. Also the warning disappears when car is stopped. 90% of the time the car is fast and responsive as it should be then with no warning it goes sluggish as if someone has stolen the turbo! Flat as a pancake and won't rev past 2500 even if i use tiptronic to change down. If you stop, switch off then back on again it cures it, (until next time). I wonder if this could be the same sensor.

 

[redfox]

car going into limp home mode

What you guys need to realise is that if a car goes into limp home mode, the concerned control units which have done this will certainly have a fault stored to tell you why it has done this. No need to wondor why, just need to plug into apropriate fault code reader!! Oh then fix the car, thats the difficult bit sometimes!

 

[Howard]

Not always ...

My CLK 320 cab has been with Olly for 5 days now , the computer says it is one thing , we change it , it doesn't help .... so we change something else , hopefully it will done soon.

Olly is a good guy and will sort it , but you can't always trust the fault codes. They give you a guideline , not a be all and end all ...

 

[BlackC55]

Howards car is testing me.....

 

[redfox]

Yes Howard i didn't mean a car going into limp home mode will have fault codes pointing to exact problem and how to fix it but definitely will give a problem area causing the fault. It is of course a daft idea that a star machine will tell you 'what is wrong with a car', although people do say that!!!