buying an o2 sensor

[airmike]

Thought I would share this, though it may not make a difference to anyone, but you never know.

I was in need of an downstream o2 sensor for my 99 seville. After checking rock auto, ebay and amazon..the lowest price ac delco was at amazon. It showed up in the AFS 98 box in 2 days but the connector didn't match. So after much double/triple checking I decided that I really had ordered the correct part# and called amazon. They were very nice and over-nighted me a replacment. Same part# hopefully the correct part in the box. Nope, exact same part in exact same correct # box (all ac delco). At that point I am really doubting myself so I went to the local caddy dealer and had them get me one. It showed up the next day with the same part# in the same box, but guess what, its got the correct part in it! Called amazon again and once again very cordial. They sent me free postage and happily refund my money. I spent a couple hours trying to find a sensor that matched the ones in the amazon boxes and never got quite exact, but they sure looked like the ones for toyota. Amazon called back an hour or so later and seemed very interested in trying to find what the sensors in their boxes actually fit. I seriously doubt they were even ac delco parts. They didn't come packaged the same (though they may just be for a different model). If the connector fit I would have put it on the car and never known any different. I suppose all the online dealers have to deal with counterfeiters. I sure hated to spend $90 for one that was supposed to be about $35 online. These are the ordered ones.

and the original

[Cadillac Jim]

An obvious counterfeit. Lots of entrepreneurs get stung by counterfeiters because they look for bargain bulk buys for their inventory, and often they don't have the resources to research their suppliers.

It could have been worse. If it had fit, you would have driven with it, with unknown effects on your car, particularly your catalytic converter.

[Logan]

Wow...blatent fake. AC Delco parts have been copied for years. Mostly stuff like oil filters.

AC Delco may want to hear from you. Bet they would like to hear about fake AC Delco parts thru Amazon..

Amazon really is just a distributor. They either have a pallet of them sitting at their distribution center or they send out a drop ship order. That said, they have a very good the-customer-is-always-right return policy.

[KHE]

The part from Amazon is fake but what are the clues? The "457" stamped on the flat of the hex?

I have replaced the pre-cat O2 sensor on the STS twice and am now wondering if the replacements are counterfiet.

[airmike]

I really don't know how to tell a fake. The replacement amazon sent has 095A stamped in the same place. As you can see the original has the afs98 on the side of the housing, but I wouldn't doub't they change markings after 16 years. I didn't look over the new one from the dealer to check for markings. If I get it back on the lift some time hopefully I will remember to take a look. As of now I have no check engine light and it seems to be idling better.

The amazon parts were never gonna work with the incorrect connector, so why would anyone counterfeit with an improper connector?