I wish we had a sub forum or other vehicle realated questions. I have a 03 bonneville has the 3.8 in it. Its giving me fits, it started with being kinda sluggish stumble of idle, over time it got worse then started having a mid throttle miss to the point it had a hard miss trying to pass and would flash the check engine light, the check light code was the po172 bank 1 rich. I changed out the plug wires were factory, fixed the hard miss now it runs great like a bobcat with its tail on fire, nice strong, power is back, had check light turned off. Drove it a few days, put about 150 miles on it, dam check engine light back on, stopped had it pulled the darn po172 is back again. Autozone said could be the o2 on that bank reading something wrong, but I am not going to start dropping 50-100 dollar sensors in it trying to find that one that setting the po 172. It has some iridium plugs in it not sure how many miles they have them, want to put new ones in but at 50 bucks a set I can't do that, plus these look ok. There has to be something or a reason its setting the rich bank 1. If I could get some GOOD injector cleaner like what shops use to put right into the fuel pressure test port would try that and clean up the injectors and see what happens but where do you get that kind of injector cleaner? I did watch a vid where a guy removed his injectors made up a adapter to fit a spray can and applied 12volts to teh injector to open it to clean it, I do not want to do that either as my fuel rail has to come out to get injectors out don't want fuel leaks. The FPR is fine its not leaking by I removed the vac line and ran it a good 5 min no fuel came so it has to be fine. I have googled the po172 and stuff to check. But everything is fine, maf is fine replaced it back in about feb this year. I have thought about removing the throttle plate and getting some carb cleaner and a toothbrush and scrubbing it down, I took it off once before last year and it was nasty dirty took a screwdriver carefully cleaning the crud off, didn't get it all. I can't just go toss high dollar parts on it hoping to find the one casusing the rich code on bank 1.