HELP! Engine revving up and down at tick-over
Thread Starter
Junior Member
Joined: Apr 2011
Posts: 64
Likes: 1
From: Blackburn, UK
clk 230k 6-speed cabriolet
HELP! Engine revving up and down at tick-over
Hi All,
My clk 230k has acquired a fault. When fired up, instead of ticking over as normal, it's revving up to about 2000 rpm then dropping back down to tick-over, as soon as it drops down it revs up again to 2k. It's as though the accelerator is constantly being pressed.
The frequency of the revving is about ever 2 seconds. Since it's done this the CEL has now pinged on.
It's happened about a year ago and I just disconnected the battery for a few hours to reset the ecu and the problem went away. Tried that this time and no joy.
Anybody any ideas?
My clk 230k has acquired a fault. When fired up, instead of ticking over as normal, it's revving up to about 2000 rpm then dropping back down to tick-over, as soon as it drops down it revs up again to 2k. It's as though the accelerator is constantly being pressed.
The frequency of the revving is about ever 2 seconds. Since it's done this the CEL has now pinged on.
It's happened about a year ago and I just disconnected the battery for a few hours to reset the ecu and the problem went away. Tried that this time and no joy.
Anybody any ideas?
Thread Starter
Junior Member
Joined: Apr 2011
Posts: 64
Likes: 1
From: Blackburn, UK
clk 230k 6-speed cabriolet
Hi,
Just an update. Took it to my mechanic yesterday, plugged in the code reader (of which there were loads of fault codes). Cleared them all so we could start a fresh and see what fault code came up, and resetting the OBD has cured the fault. Not impressed as I still don't know what was wrong.
Just an update. Took it to my mechanic yesterday, plugged in the code reader (of which there were loads of fault codes). Cleared them all so we could start a fresh and see what fault code came up, and resetting the OBD has cured the fault. Not impressed as I still don't know what was wrong.
MBWorld Fanatic!
Joined: Mar 2008
Posts: 1,232
Likes: 168
From: Glasgow, Scotland, UK
SL 350 R230 (3.7L with AMG Speedshift autobox)
Hi,
Just an update. Took it to my mechanic yesterday, plugged in the code reader (of which there were loads of fault codes). Cleared them all so we could start a fresh and see what fault code came up, and resetting the OBD has cured the fault. Not impressed as I still don't know what was wrong.
Just an update. Took it to my mechanic yesterday, plugged in the code reader (of which there were loads of fault codes). Cleared them all so we could start a fresh and see what fault code came up, and resetting the OBD has cured the fault. Not impressed as I still don't know what was wrong.
I wonder if the MAF would cause this ?
Thread Starter
Junior Member
Joined: Apr 2011
Posts: 64
Likes: 1
From: Blackburn, UK
clk 230k 6-speed cabriolet
Hi,
No, it just keeps on revving itself, even when you're driving. It's as though one sensor is saying it's revving too high and some other throttle control is saying not enough and just keeps going round in the same pattern.
No, it just keeps on revving itself, even when you're driving. It's as though one sensor is saying it's revving too high and some other throttle control is saying not enough and just keeps going round in the same pattern.
MBWorld Fanatic!
Joined: Mar 2008
Posts: 1,232
Likes: 168
From: Glasgow, Scotland, UK
SL 350 R230 (3.7L with AMG Speedshift autobox)
PS My number plate would look good on your car !! fancy buying it?
Thread Starter
Junior Member
Joined: Apr 2011
Posts: 64
Likes: 1
From: Blackburn, UK
clk 230k 6-speed cabriolet
Hi,
The MAF was fine, I fit a new one just to see and it made no difference.
I guess there's a glitch in the software on my ECU.
Thanks for the offer of the plate but I prefer mine as my name's Alex J. Yates.
The MAF was fine, I fit a new one just to see and it made no difference.
I guess there's a glitch in the software on my ECU.
Thanks for the offer of the plate but I prefer mine as my name's Alex J. Yates.
Trending Topics
MB World Stories
The Best of Mercedes & AMG
Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun
Verdad Gallardo
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Verdad Gallardo
8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine
Verdad Gallardo
Flawlessly Restored Mercedes 190E Evo II Heads to Auction
Verdad Gallardo
Electric Mercedes C-Class Unveiled: 11 Things You Need to Know
Verdad Gallardo
Mercedes EQS Gets A Major Update: Everything You Need to Know
Verdad Gallardo
5 Underrated Mercedes-Benz Models That Don't Get the Love They Deserve
Verdad Gallardo
Mercedes 300D Has Pushed Well Past 1 Million Miles and It Ain't Stopping
Verdad Gallardo
10 Most Reliable Mercedes-Benz Models You Can Buy Used
Verdad Gallardo
Newbie
Joined: Nov 2017
Posts: 2
Likes: 0
Chrysler Crossfire
I have what sounds like a similar problem with my Crossfire that has a MB 3.2 engine. I've cleaned and replaced the MAF that seemed to fix the problem but only temporarily. I also had a shop clear my codes but the problem comes back and goes away. And it's always on or off - nothing in between and the revving doesn't start or stop while the engine is running. It either runs normally on start up or revs wildly on startup.
When it revs up and down to about 2500 RPM, it's rougher than normal so it doesn't seem to behave as if the throttle sensor is wonky.
Wondered if your problem stayed cleared up after the reset or if it returned and you found another solution.
When it revs up and down to about 2500 RPM, it's rougher than normal so it doesn't seem to behave as if the throttle sensor is wonky.
Wondered if your problem stayed cleared up after the reset or if it returned and you found another solution.
Thread Starter
Junior Member
Joined: Apr 2011
Posts: 64
Likes: 1
From: Blackburn, UK
clk 230k 6-speed cabriolet
I have what sounds like a similar problem with my Crossfire that has a MB 3.2 engine. I've cleaned and replaced the MAF that seemed to fix the problem but only temporarily. I also had a shop clear my codes but the problem comes back and goes away. And it's always on or off - nothing in between and the revving doesn't start or stop while the engine is running. It either runs normally on start up or revs wildly on startup.
When it revs up and down to about 2500 RPM, it's rougher than normal so it doesn't seem to behave as if the throttle sensor is wonky.
Wondered if your problem stayed cleared up after the reset or if it returned and you found another solution.
When it revs up and down to about 2500 RPM, it's rougher than normal so it doesn't seem to behave as if the throttle sensor is wonky.
Wondered if your problem stayed cleared up after the reset or if it returned and you found another solution.
Newbie
Joined: Nov 2017
Posts: 2
Likes: 0
Chrysler Crossfire
Thanks.
