E420 DTC 6 0n Diagnostic Module
 

I'm getting an erratic idle. No check engine light, but when I pulled the codes, I got a DTC 6 on the diagnostic module (socket 19) of the 38-pin connector.

I reset the code and the problem seems to have gone away (at least for now). It has been raining here for several days and unusually humid for Arizona. The book says to "test electronic accelerator." Anyone know how to "test" it?

I'm hoping that it could be something cheap like a neutral safety switch?

I hope it's not the dreaded $1800 Electronic Throttle Actuator. Check that the wiring harness is intact, but that's not cheap either. I think it's giving you an ETA fault, hope not.

The ETA was rebuilt twice by the previous owner. The wiring harness has been changed too. Although I'm not getting an ASR light, I'm hoping the neutral safety switch is the culprit. Of course, Bernanke and Geithner are "hoping" that the economy will pick up too.