aguawaters

Hello all, Brand New mercedes owner I just picked up an E 55 AMG and im having problem. The car starts up fine and runs as it should, but when I put my foot down it will go how its supposed to and then soon after it will stop pulling hard. It drives like a corolla and at a stop light it idles rough like a truck.

If I restart the car, all is well and it drives how it should. it’ll pull how its supposed to but then after one or two pulls it will do that thing again where it drives like a camry.

I’m not too familiar with MB i’m normally a bimmer guy so this is my first benz, any help or ideas would be appreciated. Also should be noted that the car had a bad battery (the one in the trunk) which i just changed but that didnt solve the problem.

Thanks for any Responses guys

machild

Really ought to have a scan done with the MB Star system to see what it says about the car.

aguawaters

Yea I have an appointment a local MB tech that this car used to go to on tuesday

bbirdwell

I concur with the need to scan the car. My first thought is you have a bad heat exchanger coolant pump. It is located under the bumper passenger side front of the car next to the heat exchanger core. You can test it using a diagnostic system. Search in the forum and you will find multiple posts and threads on this.

aguawaters

UPDATE:

Got clthe car scanned and it is ahowing misfire codes, according to the tech. I changed the Ic pump over the weekend and that didnt solve the problem, so I’ll start with the spark plugs, also I am hearing an o2 sensor could be the cause of the codes, i believe there are 4 on this car is that corrrect? i may change the spark plugs and ignition coils first though.

machild

Which cylinders did they tell you were misfiring? They would have specifically known. With that knowledge you can swap the coils between known good firing cylinders with the misfiring cylinder to confirm whether the coil is causing the misfire. Misfires can come from a number of things and the coil is just one possibility.

aguawaters

Its cylinder 3 & 6 i believe he said athough dont quote me i should have taken a note. Im actually considering buying my own scan tool since i plan to keep this car for a long time. any suggestions for a good scan tool for MB

regarding the misfires i think im going to at least change the plugs and see does that make a difference.(a shop quoted me $980 to change my plugs... i laughed)

bbirdwell

Buy and install the Bosch spark plugs. You will need a spark plug boot removal tool to pop the spark plug wires off of the spark plugs. You will need to unbolt the coil packs for easier access to the spark plug wires and plugs. Plan on about 2 to 2 1/2 hours to change all 16 spark plugs. Be advised the spark plug wires are different lengths so if you ever remove all the spark plug wires lay them out in the order in which you remove them so you can put the proper spark plug wire into the proper spot. Heck, if you're replacing the spark plugs just do all the wires at the same time.

machild

No other tool can do that which the MB Star system does. That is what I own and all that I will use. Of the other tools some do more some do less but none do as much. While the Star system is more expensive, it will pay for itself the first couple of times you use it.Especially if you are a serious DIY.

E55Greasemonkey

What kind of "tech" worked on your car and can't tell you what's causing the misfires? Throwing parts at it is seldom a wise choice. You're already going down the rabbit hole by replacing all the coils.

bbirdwell

E55greasemonkey knows what he is talking about. He gives good advice. Listen to him.

feeshta

I would just suggest replacing the Intake Air Temp Sensor while you are at it. Relatively inexpensive, and a very easy job to replace. They tend to progressively degrade which results in the computer thinking the intake temps are higher than they are in reality, which throws off Air/Fuel ratio. Was pretty shocked how much better my car ran when I changed it earlier this year. It also seems to have cured a random no start issue I was having very rarely. Unlikely to be root cause of your issue, but could be a contributing factor.