Q: I hear a knocking sound upon acceleration

Hello. If the engine has never been overheated then it is typically caused by a failing intake manifold gasket. This is very common on this engine. In order to determine what the issue is, a mechanic would typically do a...

Hello. From what you describe, it sound like your transmission is slipping. The first thing to check would be the transmission fluid level. If the level is low, it will need to be topped up to the full level. If...

The O2 Sensors or the Mass Airflow Sensor (https://www.yourmechanic.com/article/symptoms-of-a-bad-or-failing-mass-airflow-sensor) may be bad. The list can go on. The engine computer will need to be tested and all codes diagnosed (https://www.yourmechanic.com/article/how-do-i-look-up-what-different-codes-mean). Since you drove the vehicle for a year with it...

Hello. Normally, the cause of this problem is that the door lock switch is sticking or has failed completely. The door lock switch is located in the door jam, usually near the door latch. When the door lock switch gets...

Hi there, thanks for writing in about your 2011 Mercedes E550. This sounds like potentially a bad crankshaft sensor (https://www.yourmechanic.com/services/crankshaft-position-sensor-replacement). I would recommend having the car scanned to see which trouble codes show up.  More than likely, there will be more...

This is likely a brake light switch problem (https://www.yourmechanic.com/services/brake-light-switch-replacement). I would suggest testing the brake light switch which should be located down by the brake pedal. This may also be a computer problem as well as indicated by the other...

I believe your "no crank" issue is the passlock security system has locked things down because of what it perceived as a "battery swap". If the car restarted after the jump as you indicate, the ECM is probably OK. The...

The temperature gauge may not go up to operating temperature if your engine thermostat is stuck in the open position. If the thermostat is stuck open your engine may never get up to normal operating temperature and this will cause...

The ABS and AdvanceTrac systems share the same sensors and can turn on the service lights for both systems at the same time if there is a problem in one of the systems. When the ABS or AdvanceTrac light is...