Hello,
I am new to this forum so please bear with me.

I daily drive a 2002 E430. The last couple days I've been having an issue where seemingly randomly while I'm driving I lose all power from the engine (it keeps running) and it stops responding to the pedal at the same time as the SRS light comes on. This is my signal to get to the side of the road because a few seconds after the power loss and SRS light comes on, all of the dash lights come on and I lose power steering as well. Turning the engine off and waiting a few seconds before restarting it usually gets me going 0.5-1.5 miles before having the issue again.

It also seems like the throttle has a mind of its own, as when I'm in drive and at a red light for example the RPMs won't just sit at 1000 like normal but quickly fluctuate between 900 and 1100. If the car is in park or neutral when this is happening it instead fluctuates much more and any force applied to the throttle sends the RPMs up very fast and it looks like its heading for redline but I turned it off before It reached that far. Even tapping the pedal does this because the RPMs don't seem to come back down on their own.

I scanned the codes after the first couple times this happened and in addition to some emissions related codes got:

• P0101 - Mass Airflow Sensor
• P0123 - Throttle/Pedal Position Sensor
• P0120 - Throttle/Pedal Position Sensor/Switch A Circuit Range
• P0221 - Throttle/Pedal Position Sensor/Switch B Circuit Range

I replaced the pedal position sensor with a Mercedes part and the MAF with a Bosch one and cleared the codes and drove around town a couple miles with no issue. However, but the exact same issues happened today and it would happen again every mile or so after I restarted. Upon reading the codes I again got:

• P0120 - Throttle/Pedal Position Sensor/Switch A Circuit Range
• P0221 - Throttle/Pedal Position Sensor/Switch B Circuit Range
• P0101 - Mass Airflow Sensor

I cleared the codes again and managed to get home while driving super careful and slow.
I am now at a loss as to what my next steps should be so any help would be much appreciated.
Thank you for your time.

Possible needs throttle position reset. Take a look at the two links, might be of assistance and is easy to perform.
If no joy, hook the car up to STAR and monitor the actual values of the throttle position sensor. Could be as simple (yet hard to find) bad contact between one of the pins and sockets in the circuit.

https://mbworld.org/forums/m-class-w...tor-issue.html

https://mbworld.org/forums/m-class-w...ml#post2321983