Proper Idle Speed

[fritzintn]

I recently picked up an 88 M3 after quite a bit of hunting. The motor was rebuilt around 7k miles by the previous owner. Anway it seems to idle a bit higher than I was expecting, around 900rpm or so when warm.

After reading quite a few posts regarding ICV and DME failure I've started to get a bit worried and none of the posts directly mentioned what was a 'good' idle speed.



(hopes searchy doesn't yell at me )

[TeamM3]

base idle is suppose to be set to 880 +/- 50 rpm

as described in the archives :p, to set base idle:

engine warm, proper operation, no intake leaks, all electrical & AC off, good air filter

disconnect throttle switch connector from wiring harness

on harness side of connector insert pins/wires/etc and ground all three pins in the connector together

adjust base idle, adjusting screw is located between valve cover and fuel rail just above the "M" in the "BMW M Power" lettering on the valve cover

technically you would do a throttle body air screw synch and set the CO afterward, then recheck the base idle again

[Dean]

I'd also perform a valve adjustment before the 3 procedures that TeamM3 mentioned. These adjustments are really important to get an S14 running right.


Dean

[dllance]

^^^^^^^^^