Hi, Im new to the forum and I dont know if this is any help to anyone but it worked for me...... My Volvo was hunting on idle for the past six months. After checking the sensors I put the problem down to the electronic trottle. This morning I rang the volvo dealer where I bought the car 5 years ago with 99000 miles on the clock. The expert told me that before I replace the unit at a cost of 1000euro to drill a tiny hole in the air intake of the module, buy a can of induction cleaner, run the engine and over a 1/2 hour period spray quick blasts of the cleaner into the throttle body. It mixes with the air before it reaches the throttle. Guess what, IT WORKED..problem solved without using one tool at a cost of 8euro. I hope this helps someone. Good luck.