Howdy all,

I've tried to be self-sufficient using this great resource, but have come to the end of my ability to troubleshoot my very rough running 1995 E320. To make matters worse, I'm on the road...850 miles from home, and away from a known good mechanic. Any suggestions on what I should try next would be greatly appreciated.

The problem: Car runs incredibly rough, and barely idles. Power is noticeably reduced. The problem started immediately the other day, and has not gotten better or worse. The engine miss and sputtering is evident at all RPM's and temperatures, although it's a little more pronounced at lower RPM's.

The car had the main wiring harness replaced last year, and has run fine since.

In searching through the forums, I discovered the coil/spark plug boot issue on the M104, and ordered/replaced all three from Phil, along with the plugs. Made no difference.

Next, I built Arthur's Radio Shack code scanner. First time through, I pulled a code #11 on pin 14 ("Closed throttle recognition signal to engine control module"). However, upon clearing the codes, it has yet to return. No other codes on pin 14, and none on pin 3 or 8.

I've looked for vacuum leaks, but not being familiar with the engine, I'm not sure where all to look. There is a two-tone electrical humming noise audible under the hood when the key is on (engine off) that I don't recall being there before, but I'm not certain...it may be normal.

Any thoughts?