I have replaced the mass air flow sensor on a 2006 E350 with 160,000 miles, twice and the check engine light continues to come on. About a month ago prior to replacing the sensor again I was on the highway and the car started to act like it was having a misfire. I replaced the mass airflow sensor again and also replaced the plugs as they were due. Test drove the car and it ran fine. Then got onto the highway got up to 80mph and it began to run rough like it was having a bad misfire and ran rough all the way to my home about 30 miles. Now the problem is intermittent with a slight jerking of the engine. I have checked for vacuum leaks (that doesn't mean I didn't miss it). A couple of days ago I pulled into a parking lot and the rpm began increasing on its own. Only did that one time. It is not showing any codes for a bad coil as I have thought of replacing those and I even tried replacing the air filter to see if that would help. Outside of this problem the car runs great. I am trying to avoid dumping a lot of money into an old vehicle but it is a great second car.

 

Are you using a genuine OEM MAF from bosch or generic brand?

 

Yes. This last one was a Bosch from a dealership. I wanted to make sure it was what was needed for the car.

 

Did you scan for saved codes and RESET/erase the code after the replacement maf was installed?
Also note note, it takes a couple of hundred miles for the relearning of the new maf when it's replaced.

 

That's correct - scan for codes in about 100 miles or so and see what comes up.