My '01 E55 has ~110,000 miles on it. It started running very rough recently. Terrible gas mileage and throwing a 0100 code consistently (erase it, starts up without it, then comes right back).

Has anyone had any experience diagnosing a 0100 Code (MAF or VAF A Circuit Malfunction)?

Replaced the MAF about 12,000 miles ago (whole thing with a Bosch part; not just the insert). Since I started getting the 0100 code I took out the MAF and cleaned it with CRC MAF cleaner (didn't take the MAF apart).

Any help is appreciated.
--Ed

 

did you replace your airfilter as well? Chances are you will have to get another MAF and new air filter.

 

a circuit problem,not a cleaning problem.You need to check power to the maf,any loose or frayed wires,Make sure the socket is plugged in.Bosch part off ebay or a real bosch part from someplace like autohausaz.com.?Someplace the maf system is not getting the whole 5 volt signal,,,,,you need to locate where.Any friends near by to swap out the maf and see if it has a gone kaput circuit?
ohlord

 

The one I replaced ~12k miles ago was a Bosch MAF from Autohauz.com. I have a neighbor with a 2001 E320...will it have the same MAF???

 

I replaced the Air Filters about 2 months ago.

 

you would need one from an E430 or another e55.

 

Tried disconnecting the battery for an hour...no help.

 

your maf is kaput replace it and your air fliters

 

PO100 IS a circut malfunction (ie: loss of power/communication).

Check the wiring and connections.

 

Replaced the MAF this morning. Cleared codes and took it for a 15 mile drive. No CEL. Great performance and 19.5mpg.

 

as suspected ---- swap out the maf and see if it has a gone kaput circuit?---
The Maf circuit was kaput and Autohausaz.com replaced it no problemo
Now you can get back to kickin butt and takin names That has got to feel great!

 

Yep...feels great. Now on to the next challenge. Slight vibration at idle. Getting ready to replace tranny mount (already did motor mounts).