Lopping (Page 1/1) michael jatcko JUL 21, 11:39 AM Why does my 86fiero lop at low speeds, ladles fine, and runs great at higher speeds. V6 CharginPegasus88 JUL 21, 02:00 PM Two things that come to mind are timing and IAC. If the timing is too far into retard, it will lope more (advanced, it will run faster) though the ECU should control this for the most part under normal conditions. I believe factory timing setting for the V6 is 10* BTDC. Also, if the IAC is running slow, you could be getting too much air past the throttle at idle which will make it stumble. Both are relatively easy to check.