It could be the Idle Air Control Valev, IACV, which adusts idle when load demands are changed on engine.
However, the fact that is is using more gas is usually indicitave of a failed O2 sensor. The O2 sensor is one of if not the most important part indeterming the air/fuel ratio. If it fails, it will either send a voltage signal to the ECU for chagnges in fuel management. They usally fail with the signal being for more fuel. Also, if you have anexhaust leak near an O2 snesor, it will think the mixtue is lean and tell the ECU more fuel is needed.
Try replacing the O2 sensor if it has never been replaced. With the age of the vehicle it would be a good idea anyway. Get some good injector cleaner. Most cleaners do not work well. There are only 2 that I reccomend; SEA FOAM or BG44K. You might have to go to a service station to get them and I would suggest getting 2 cans. They work so well you will need to change the oil afterwards from all the gunk it will clean out.
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Sunday, September 4th, 2011 AT 9:18 PM