Car jerking during gear shifting while flooring the gas pedal
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Joined: Aug 2009
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Car jerking during gear shifting while flooring the gas pedal
Hello everyone. I'm about to get a used 50k km run 2009 MERCEDES-BENZ S 320 CDI (221.122) model. The owner is a friend and has given me the car to use for a few days before I decide to buy it. I noticed one problem and I'm concerned about it. The problem is -
In cold start, car jerks in S and C gear mode when accelerator is floored/pressed fully. In light and linear acceleration there are no problems. In M gear mode with paddle shifting, the problem does not happen. After a while of driving(10 mins) in linear acceleration and then flooring the accelerator the problem does not happen for hours of driving and goes away. Happens only during cold starts in the morning or after the car has been started after a while. Any idea on why this is happening? Transmission is 7G-Tronic (coded 722.9) . Engine is V6 DIESEL ENGINE OM642, Thanks in advance for any help you are able to provide!
In cold start, car jerks in S and C gear mode when accelerator is floored/pressed fully. In light and linear acceleration there are no problems. In M gear mode with paddle shifting, the problem does not happen. After a while of driving(10 mins) in linear acceleration and then flooring the accelerator the problem does not happen for hours of driving and goes away. Happens only during cold starts in the morning or after the car has been started after a while. Any idea on why this is happening? Transmission is 7G-Tronic (coded 722.9) . Engine is V6 DIESEL ENGINE OM642, Thanks in advance for any help you are able to provide!
Last edited by wannabelean; Apr 9, 2018 at 10:45 AM. Reason: Wrong word
Senior Member
Joined: Dec 2013
Posts: 314
Likes: 35
From: New York
2010 CL550
Hello everyone. I'm about to get a used 50k km run 2009 MERCEDES-BENZ S 320 CDI (221.122) model. The owner is a friend and has given me the car to use for a few days before I decide to buy it. I noticed one problem and I'm concerned about it. The problem is -
In cold start, car jerks in S and C gear mode when accelerator is floored/pressed fully. In light and linear acceleration there are no problems. In M gear mode with paddle shifting, the problem does not happen. After a while of driving(10 mins) in linear acceleration and then flooring the accelerator the problem does not happen for hours of driving and goes away. Happens only during cold starts in the morning or after the car has been started after a while. Any idea on why this is happening? Transmission is 7G-Tronic (coded 722.9) . Engine is V6 DIESEL ENGINE OM642, Thanks in advance for any help you are able to provide!
In cold start, car jerks in S and C gear mode when accelerator is floored/pressed fully. In light and linear acceleration there are no problems. In M gear mode with paddle shifting, the problem does not happen. After a while of driving(10 mins) in linear acceleration and then flooring the accelerator the problem does not happen for hours of driving and goes away. Happens only during cold starts in the morning or after the car has been started after a while. Any idea on why this is happening? Transmission is 7G-Tronic (coded 722.9) . Engine is V6 DIESEL ENGINE OM642, Thanks in advance for any help you are able to provide!
