Ok guys, I've just about exhausted all ideas I've had here. For the past month or so I've been fighting the crazy P0171 code. It has resulted in new, coils, plugs, wires, - cleaned the MAF sensor, checked and inspected the egr tube. Replaced the egr solenoid and valve. Replaced all vac lines and finally the fuel pressure regulator. And thank the maker, the light has been off for almost a week now. Before when it would go off it would re-appear the very next day, so after many frustrating failed attempts I'm somewhat optimistic that I've beaten the code. Oh yeah in case Bill reads this, the battery cables were inspected thoroughly. Was a small amount of corrosion on the floor board where the negative cable was grounded, but other than that the cables actually looked new (slid the rubber boot off and everything). Anyways code has been off, but throughout this entire ordeal I've been getting a weird idle. Its not consistant. Sometimes when I'm at a light the car will idle like a champ. Then other times the car will actually shake (kind of pulsate) a little at idle, like when I'm at a stop light. Thing is the RPMs never fluctuate. All the gauges read normal. In fact if it weren't for the car shakin you wouldn't know anything is wrong. This is actually getting to be more frustrating than the SES light, because with all the new parts I've been throwin at her the car runs better than it ever has. Fuel economy went from low 17'* to high 19'* and will break 23 on the highway. I just had the exhaust inspected today for leaks. I was told for an 11 year old car that the exhaust was holdin up pretty good and that there were no signs of leaking or cracks anywhere. So I'm curious to see what you guys think.
2000 Bonneville SSEi aka "Eva"
"Everybody is fast in a Bonneville"