I recently bought my second Bonneville. My first was a 92 SE. My most recent purchase was a 2000 Bonneville SE. Had 101k at purchase and now has 111K. I have had a bunch of things go wrong. My most recent problems are: Traction control just went out today. I suspect it is a bad sensor in the wheel bearing hub. Happened right after I hit pot hole. No ABS lights on my cluster, just "Trac Off". But before that on my way to work, my low tire pressure warning came on. Checked tires and were fine. All within a couple of pounds. So I hit the reset. I'll take to a GM dealership to confirm. My main problem that has me stumped, and my mechanic( who is not a GM one but a whole lot cheaper). It started about 3 months ago. The car would randomly cut out and jerk violently. Took to a GM mechanic and he told me it was my Mass air flow. Thats what his diagnostic told him. Would have done it myself but lack of heated garage and dead of winter I had my regular mechanic fix it. Well that did the trick. No more random cut outs. After I got the car back from him my Service engine soon light came on so I called my regular mechanic back and he told me that it had some 02 sensor codes. don't know what the codes were so I installed 2 new 02 sensors. I bought bosch non universal ones from autozone. Engine light disappeared for 3 days then came back on. Went to autozone again and had them clear the codes. 3 days later the light was back on. So I took it back to him and waited while he worked on it. He did not have time to dig deeper but said he getting some kind of code about the 02 sensor heater circuit on both. He checked all the fuses and they were fine. Called the GM dealership and they told me it could be the bosch sensors I put in. Can anyone shed some light on this before I spend more money in diagnostic fees?? The car runs fine and my gas mileage is around 17mpg with 50/50 city/highway. By the way I am still on the original battery. Guess I'm pressing my luck.

Your gonna hear this alot so I'll just be the first...It'* the Bosch sensor. I replaced mine with AC/Delco and it finally stopped.

Yup - AC/Delco or Denso sensors only. Nothing else seems to last.

" I replaced mine with AC/Delco and it finally stopped"

Ops! I did the quote thing backward

The Bosch sensors last just a few months at most. If you got the SES code for the O2 sensor, then yes..that is likely the cause...as is your low MPG.