Vibration at idle 2009 e350
12-27-2023, 01:01 PM
#1
Junior Member
Thread Starter
Vibration at idle 2009 e350
Hello everyone,
I have a 2009 e350 with 130k miles. The car is great. The only issue I have is a slight vibration at idle. This usually becomes apparent after I turn off the car and turn it back on (the first drive of the morning is pretty smooth). When it vibrates, the RPM's do not change. The needle is stable and never fluctuates. I have scanned it and found codes P0300 an P0302. I have replaced the spark plugs and coil pack for cylinder 2 but the problem persists. Mercedes took a look at it about a year ago and told me there was some oil in the ECU from the magnets. I not particularly convinced this is the problem, as they cleaned the oil and the problem didn't go away. As of now, I have the following theories:
1: Faulty fuel injector
2: Vacuum leak somewhere (although I'm not seeing any leak)
3: MAF or airflow problem (although I don't know why it would be exclusively on cylinder 2)
4: Worn exhaust valve (which I pray it is not)
I have not done a compression test yet or checked the fuel injector. When accelerating, the car is perfect. Fuel mileage also hasn't changed.
Any thoughts or advice on what I should look at next?
I have a 2009 e350 with 130k miles. The car is great. The only issue I have is a slight vibration at idle. This usually becomes apparent after I turn off the car and turn it back on (the first drive of the morning is pretty smooth). When it vibrates, the RPM's do not change. The needle is stable and never fluctuates. I have scanned it and found codes P0300 an P0302. I have replaced the spark plugs and coil pack for cylinder 2 but the problem persists. Mercedes took a look at it about a year ago and told me there was some oil in the ECU from the magnets. I not particularly convinced this is the problem, as they cleaned the oil and the problem didn't go away. As of now, I have the following theories:
1: Faulty fuel injector
2: Vacuum leak somewhere (although I'm not seeing any leak)
3: MAF or airflow problem (although I don't know why it would be exclusively on cylinder 2)
4: Worn exhaust valve (which I pray it is not)
I have not done a compression test yet or checked the fuel injector. When accelerating, the car is perfect. Fuel mileage also hasn't changed.
Any thoughts or advice on what I should look at next?
