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?

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1993 400E, 256,000 miles (totaled)
1994 E420, 200,000+ miles
1995 E420, 201,000 miles