I've got a 99 MTX V6. Just recently it started idling kinda rough and its got 82k miles so I figured I'd go ahead and put plugs and wires in it. Got them in now (Belden Wires from NAPA and Bosch Ir Fusion Plugs) and it helped for a little while but the rough idle has returned :facepalm:. I was going to just dismiss it as a bad tank of gas until I noticed this evening that the gauge lights were dimming slightly at idle and get brighter when the engine is revved. I fear now it might be the voltage regulator. I work at the Sears Auto Center so I'm gonna use our tester at work tomorrow and see how the diodes check out and everything. I've cleaned the throttle body and I run a bottle of injector cleaner through it when I change the oil so I doubt it's fuel related. Just wondering if anybody has had similar symptoms and what it turned out to be. Thanks!