This past Friday I had a mechanic (thanks for the recommendation Terry) run a diagnostic on the computer system. He didn't provide any concrete conclusions, but recommended that I replace the coolant sensor and voltage relay. He further stated that with a bad voltage relay, the air/fuel mixture becomes very rich, which would cause my poor fuel economy. The problem is that I don't know what he means by voltage relay. I called him today and, I guess being to busy to talk, he said to ask at the dealership and they will know immediately. Is it the ovp relay he's referring to? I tested the ovp as per the instructions at Help!! Need OVP plug schematic!, post #58, and got supply voltage to pins 30a, 87E, and 87L just as it describes. Could he have meant the EGR relay? My EGR valve hasn't worked since 4 or 5 days ago. Would the EGR relay control or have any effect on the intake flap? Unfortunately, I don't know which coolant sensor to check/replace either? I was told that it is not the two-pinned blue one to the left of the fuel filter, and I recently replaced the 4 pin sensor beneath the intake manifold with no improvement. Are there any others? I've heard there are three coolant sensors, but I'm not sure if my car is set up the same. Since a coolant sensor may play a significant role here, I figured I'd mention that I recently noticed that my auxiliary fans don't work either. I tried jumping the two pin coolant sensor, but that did nothing. Sorry for the cluttered information. I don't mean to try to have all my cars issues solved in this thread, but I just thought that knowing this could in some way help get to the bottom of this.