I got a hold of one of these code readers to see if i can solve the running problems of my e36 325i. It passed its mot but it still has a high/rough idle going from 1k to about 2k constantly and it seems to be a bit smokey ( white smoke ).
Ok i did what the manual says. turn key but not start engine then plug it in.
How long should i leave it plugged in before FC appears? Cos i have tried a couple of times and nothing.