Got a mechanic friend that just bought a nice 98 SE that was running poorly. Needs UIM and LIM gaskets. He has done that, and now is going to replace plugs, wires, and O2 sensor. I had turned him on to this Forum when he bought the car, and he has been reading articles here. He asked me yesterday what it is that the members have against Bosch O2 sensors, as he has used them in many cars over the years and has not had any complaints. I couldn't answer his question... I just told him I know Bosch plugs are not to be used, but I thought there were differing opinions on the O2 sensor...some members have used them and found them OK, others not. So, what is the deal with them? Are they that poor in quality, or is there something about the 3800 that is not compatible with them. Just curious. :? Thanks.

iirc they just seem to go out alot quicker than most other brands of o2 sensors on these cars, bosch+ 3800= no good

I know. I had Bosch in my 2.8L Celeb. But in the 3800 i think it doesn't like them. Just like there spark plugs dont last long in the 3800'*

When many members have tried them and most have had problems, good rule of thumb is not to use them

I don't believe that we, as a group, have anything against Bosch as a company. It just seems that Bosch O2 sensors as a rule have not given consistent good results in the Buick 3800 and we have had many members here whose Bosch O2 sensors failed shortly after install.

I don't believe there has been any sort of controlled study to support our collective bad recommendation, just a large sampling of subjective results.

Right. I didn't mean to imply that the group did have anything against the company, and experience is certainly a good indicator of future performance. I just couldn't answer his question about why plugs and O2 don't work well in the 3800, and I don't know how they operate in other engines. My advice to him was to go with the Delco. I think the jury is out on the Denso.

I'm running a Denso on my 00, problem free for several months so far.

I'm a victim of Bosch O2'* here. One of many. Mine failed in less than 30 days. Worse mileage than before.

AC Delco fixed me right up. There are DOZENS of 'victims' here on this Forum over the last 5 years.

Bosch is a European company that makes and sells European parts in Europe for European cars. Can you see a pattern developing here?
When I had my Volvo 240 I read a lot of maintenance advice on Brickboard dot com from people who have owned 240s that went well over 500,000 miles. They are generally a frugal bunch there on the Brickboard and they found that you can use a Ford Escort O2 sensor for about one fourth the cost of the Bosch.
If you are keeping your European car all original then I think Bosch parts are as good as any on a European car, based on my experience. But likewise, if you are keeping your American made Pontiac all original and you want the best value for the money, buy GM parts like AC plugs and Delco O2 sensors.