Rough Acceleration
Thread Starter
Senior Member
Joined: Dec 2014
Posts: 286
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CL55
Rough Acceleration
I am getting a rough acceleration at several points in every gear. Feels like a misfire or lack of fuel delivery. It will accelerate smoothly outside of those rough points. Seems to happen primarily at 1,500 RPM but it does it at other spots as well. The condition improves as the engine warms up to the point where it's barely noticeable at operating temperature but it does not go away completely. The symptoms have been present for several months with no error lights. I have replaced all my ignition coils and both upstream O2 sensors with no improvement. I have a set of plugs I'm about to put in but short of that I'm wanting to know what else it could be.
I've read about the accelerator pedal but the symptoms dont match up.
Thoughts??
I've read about the accelerator pedal but the symptoms dont match up.
Thoughts??
Last edited by khutchinson22; Jan 20, 2018 at 11:16 AM.
Thread Starter
Senior Member
Joined: Dec 2014
Posts: 286
Likes: 4
CL55
Spark plugs replaced last night. Seemed to help significantly but there is still a noticeable roughness in the powerband. I'm not sure if theres buildup in the cylinder or valves due to plugs not firing properly or if there is another underlying issue. I've got no codes to assist but I do have a cheap scanner/phone app that gives me access to at least some information if I knew what to look for......
Thread Starter
Senior Member
Joined: Dec 2014
Posts: 286
Likes: 4
CL55
Update
I checked all the plug wires for resistance and they’re all testing fine. Hooked up a snap on scanner and can’t see real time data but no recorded misfires.
Is there any way to test the accelerator pedal sensor without replacement?
Is there any way to test the accelerator pedal sensor without replacement?
Senior Member
Joined: Feb 2005
Posts: 254
Likes: 17
From: America
CL600 2003
Could also be fuel pump, fuel filter, fuel electronic module that controls the pump... check the fuel pressure
https://mbworld.org/forums/m275-v12-...elaration.html
https://mbworld.org/forums/m275-v12-...elaration.html
Last edited by slonar21; Feb 19, 2018 at 01:35 PM. Reason: .
