Hey Robert,




Dave Stevens was very kind to reply back to me with a link to his latest post regarding this topic:

http://www.brickboard.com/RWD/volvo/1358080/940/960/980/V90/S90/940gle_high_idlehelp_run_ideas_throttle_body_adjustment_tb_tps_switch.html

He explains how to set the throttle body and the special part I mentioned is a tweaking of the linkage.

The idle air valve controls the idle by admitting more air. If the engine is getting too much bypass air from a throttle body being open too far, the engine will idle much too fast and there is nothing the ECU or the idle air valve can do about it. I had this problem with mine, and thought all sorts of things were wrong. A little test you can try to see if this is your problem works like this:
with the key off in the ignition, unplug the mass air flow sensor and disconnect it and the intake hose. Start the engine (which will now run in limp home mode and light the check engine light). With the engine running, carefully put the palm of your hand over the throttle opening the block the airflow. You'll feel the suction. If the idle comes down to something reasonable, you've found your issue. I would suggest checking the operation and adjustment of the idle switch. You'll have to readjust it if you adjust the throttle body. Try this before you spend any more money for a ECU.

Hope this helps.

Jon