Loss of drive when using kickdown
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Junior Member
Joined: Sep 2024
Posts: 22
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Loss of drive when using kickdown
Hello all . I'm new to this site and Mercedes vehicles and struggling a bit with navigating the site and the abbreviations commonly being used but I'll get there. Two weeks ago I purchased a lovely 2003 CLK 320 with an impeccable provenance with 165 K on the clock. Test drive was perfect. Since owning her I'm experiencing the following problem. When using kickdown to overtake everything works just fine for a few seconds, it changes down and quickly increases the revs, then there's what I'd describe as a violent disconnection of the gearbox . This is accompanied with total loss of drive, the engine will rev under throttle control but no drive. Taking it out of drive and back in again has no effect.The car has to coast to a near stop and then everything returns to normal.
There are no other issues to report it drives and sounds beautiful. If anyone can suggest a course of action I'd be very grateful. I'm also trying to firm down on which OBD2 diagnostics/ code reader to buy in the $300-$400 range again any recommendations would be helpful. Regards Nissrolet
There are no other issues to report it drives and sounds beautiful. If anyone can suggest a course of action I'd be very grateful. I'm also trying to firm down on which OBD2 diagnostics/ code reader to buy in the $300-$400 range again any recommendations would be helpful. Regards Nissrolet
Last edited by Nissrolet; Sep 18, 2024 at 12:18 PM.
Member
Joined: Jun 2024
Posts: 191
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E320
Hey Nissrolet, I totally get how annoying that kickdown issue with your CLK 320 can be. This kind of behavior often points to problems within the transmission system, such as a malfunctioning torque converter or issues with the transmission control module (TCM). It could also be related to sensors like the throttle position sensor (TPS) not communicating correctly with the engine control unit, causing erratic gear shifts. Additionally, low or degraded transmission fluid, or failing solenoids, might be disrupting the gearbox operation, leading to that sudden loss of drive when you push for overtaking. Accelerator pedal can also be the issue. You should probably run a full system scan to get to the bottom of this. There should be fault codes on at least one or more control modules related to this issue. Using a full system scanner like Xentry is ideal if you have access to it. I tend to use youcanic full system scanner since it’s easier and quicker for diagnostics, even though I have Xentry lying around. It can run an in-depth all-system scan and diagnostic, helping you identify the exact cause without too much hassle. Hopefully, it’s something straightforward and not too much of a headache!
Thread Starter
Junior Member
Joined: Sep 2024
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No I haven't tried replacing the pedal assembly yet . I have had a really good look at it though. From an appearance point of view it looks like new. Of course I'm not able to determine the pedal position sensor condition internally but it's working and driving smoothly in every other way. Do you know if I'm able to just replace that sensor on the pedal or do I need to replace the whole pedal assembly?
Thread Starter
Junior Member
Joined: Sep 2024
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Kickdown issues
Just a bit of an update. I found transmission fluid leak at electrical socket in the side of the gear box. I've purchased a service kit on line cost $62 . It all fitted perfectly with no issues. It all felt and looked OEM . Came with new sump gasket , electrical socket with both seals , filter , correct dip stick to manually check the transmission oil level, O ring for the fill point cap and a new tamper seal. It's cured the leak. I'm yet to test the kickdown to see if it was just the oil level. I'll report that later. For interest the auto gear change is hyper sensitive to various oil levels , a tad to little and she won't change gear , just holds in one gear and if on a slight incline won't drive at all.
I've also realised that the kickdown has been working all the time, the nasty jolt and then loss of drive occurs once I ease off the throttle . Everything returns to normal once the vehicle speed drops to approximately 20km/hr . I'm still trying to get to the bottom of that . Any views would be welcome. Regards Nissrolet
I've also realised that the kickdown has been working all the time, the nasty jolt and then loss of drive occurs once I ease off the throttle . Everything returns to normal once the vehicle speed drops to approximately 20km/hr . I'm still trying to get to the bottom of that . Any views would be welcome. Regards Nissrolet
Thread Starter
Junior Member
Joined: Sep 2024
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I'm really pleased to be able to report I've sorted and resolved the kickdown loss of drive problem. As my previous post I purchased a service kit to correct the transmission leak problem at the electrical plug connector in the side of the transmission . The next part was to get the oil level correct in the transmission box. Not as easy as it sounds , took a couple of attempts but it's correct now . Once that oil level was correct the transmission works perfectly now and no issues with kickdown. So from my limited experience I'd always say the first thing to check on these vehicles , if you start to experience any form of transmission issues would be to inspect the oil levels and the age of the oil , because it just may be that simple and save you a head full of other potentially horrendous worries . Regards Nissrolet
Newbie
Joined: Aug 2024
Posts: 6
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From: Long Island, NY
2013 SL63 AMG, 2006 SLK350 Sold, 1998 SLK230 Sold
Replaced Accelerator Pedal
OMG ii replaced pedal assembly on my 2013 SL63, what a difference!
I was experiencing safe mode several times after stomping on the pedal as well as some jerky downshifts. Thanks to this forum, I replaced pedal assembly.
Honestly took less then 10 mins!
l disconnected battery
unscrewed 2 plastic nuts holding pedal down
disconnected plug
reconnected plug on new pedal
replaced plastic nuts
reconnected Battery
Took it for a spirited drive
What a Pleasure!
No limp mode, no jerky downshifts!
$144.00 AzAutohaus
Thanks to All who posted this easy fix
I LOVE my car again😁
I was experiencing safe mode several times after stomping on the pedal as well as some jerky downshifts. Thanks to this forum, I replaced pedal assembly.
Honestly took less then 10 mins!
l disconnected battery
unscrewed 2 plastic nuts holding pedal down
disconnected plug
reconnected plug on new pedal
replaced plastic nuts
reconnected Battery
Took it for a spirited drive
What a Pleasure!
No limp mode, no jerky downshifts!
$144.00 AzAutohaus
Thanks to All who posted this easy fix
I LOVE my car again😁
