E36 M3: occasional skip at idle

[James McElroy <mcelroy@xxxxxxxxxxxxxxx>]

I recently purchased my first BMW, a 95 M3 with 63,000 miles.  I've 
wanted an M3 since the E30 M3 came out, so when a friend offered to 
sell me his pampered 95 with 2 extra sets of rims (for snow/Solo II), 
I couldn't resist.  I've put 7500 miles on the car in under 3 months.

The car is fantastic, but I've recently noticed that the engine seems 
to skip or miss occasionally when idling.  It's barely noticeable in 
the car, but you can definitely hear it if you stand near the muffler 
("mmmmmm-puh-mmmmmmmmmmmmm")

A local BMW specialist claimed the idle control valve was sticking 
(they cleaned it) and that the throttle plate had carbon build up 
(which they also cleaned) for $70 worth of labor.  The car seemed 
better for a day or so, but the skip/miss is back.

Assuming the engine shouldn't skip/miss at all, does anyone have any 
suggestions on what to check?  The car has new Bosch plugs (don't 
know what kind; they were given to me by previous owner and are 
supposedly the correct plugs for the car).  I'll be putting in a new 
02 sensor this weekend (a 60k replacement item)...

Thanks!
______________________________
James McElroy
mailto:mcelroy@domain.elided

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