Engine Performance problem
2003 Mercedes Benz C230 4 cyl Automatic 59898 miles
My car runs like it is our of gas. Whenever I accelerate fast or go up hills it jerks rough and bucks like it is out of gas. It does not matter if I'm going 2mph or 80 mph or hot or cold start the car always bucks when I accelrate and feels jerky.
I put engine cleaner in the gas twice and always use premium gas, I removed the air filter, and changed gas filter and the problem is still there and there is no check engine light on. At this point I'm clueless. Also if I'm just riding down the road and it is a flag surface and do not require much gas it run fine. Thanks
Although you have pretty low miles you may be experiencing a faulty fuel sending unit (fuel pump). This will cause the " out of gas" experience you are having. Also it is not uncommon for things like this to not throw a check engine light. Often times problems like these will require some electrical diagnosis to figure out what component is ultimately to blame. Also a faulty Mass Air Sensor may cause a similar condition and is closely associated with throttle response.
March, 4, 2009 AT 12:37 AM
I really appreciate your response and I have one more I have also went and got my car checked out at AutoZone to make sure they could not find anything on there sensor reading to see if there was anything reading out that could be a sensor even though there is no check engine light on in my car and everything came back fine. Instead of me changing the fuel pump or mass air sensor is there anyway to check to see if it is that then just paying for the parts and it not be the problem?
Because since nothing came back with the electrcial sensors I'm clueless on what this could be and hoping this is not a transmission issue? I appreciiate your response ooh and also one last thing someone had mentioned an accelerate sensor on my gas pedal ever heard of that?
March, 4, 2009 AT 11:39 AM
I absolutely agree that you don't want to throw parts at this problem because it will get real expensive real fast. In this situation what is necessary is to be able to read your mass air flow sensor values in real time, this will require some pretty sophisticated scanning equipment that can read values while the vehicle is being driven. I know this is possible with the MB Star diagnostic tool which is what your dealer uses and has the capability of reading multiple sensors at once. As for the fuel pump you can hook a fuel pressure gauge up to your fuel rail to check for proper pressure but if you are using good gas a fuel pump will be more unlikely. As for the throttle position sensor, this is typically associated with no throttle response and not the bucking and jerking you are describing. Usually what will happen is when you hit the throttle nothing happens or you get a delayed response from the motor. Personally because of the intermittentness of this, I would recommend taking this to a dealer and tell the service advisor exactly what is going on. Then ask him to have a technician ride in the vehicle with you so you can duplicate the problem for the tech (this will prevent them for sending you home with no problem found). Once you have shown the tech the when and how the problem occurs the tech will have a complete understanding of the issue at hand and will allow them to diagnose the problem without trying to duplicate the condition on their own. A dealer will have the ability to read the real time values while the vehicle is driving and when the condition occurs. This will allow for proper diagnosis without throwing parts at the vehicle.
March, 4, 2009 AT 11:42 PM
One last question does this car have any other type of gas filter other then the one that I changed under the car? I was not sure if it had one in the actual gas tank or anything that might be clogged up other then the gas pump.
April, 27, 2009 AT 4:44 PM
I had this same problem with my 2003 C230 and I had to have a " mass air flow sensor" replaced. That sensor costs around $350-$400. It solved the problem though and was worth the cost.