BAD99TA

I've noticed a steady decline in gas mileage (I haven't changed my driving habits or anything like that) recently and I'm looking to replace my O2 sensors. I'm not sure what the best route to take is. I don't have aftermarket headers on the car. From the searches I've done I see there are a few options. One being the Bosch 13111vette rear o2s that have the longer wiring harness for aftermarket headers which I don't have. The 2nd option is the AC Delco original replacement O2 sensors for 1998-2002 LS1 F-Body, Passager Side & Driver Side (Pre & Post Cat). It looks like they come with quantity 2 for passenger side & 2 for drivers side. Does this mean I need to replace a total of four 02 sensors? I'm not sure I'd need the Bosh 02s, I just want to make sure I make the right purchase and get the correct quantity. Any info from someone who's been down this road before would be much appreciated. Also if you've had a good experience buying from a particular place could you let me know as well. Thanks!

caddobass

iTrader: (1)

I have had to replace my O2 sensors twice because of failure on my 02 ss. I have talked with people that have never had a problem with O2 sensors. I do have long tune Jet Hots and no cats so I guess they get a little more heat. I use the 13111 Bosch as I was told they would take more heat better than stock.

tylerdj

iTrader: (31)

If there's a problem with your O2's it should be throwing a code.

BAD99TA

If I were to go with the Bosch 13111, how many would I need to purchase? It looks like they are about $68.99 a piece.

tylerdj

iTrader: (31)

With stock exhaust you should just go with a direct replacement...there's not really a need to use the 13111. There are 4 O2's total...1 before and 1 after the cats on both sides.

BAD99TA

There's no SES light on or anything like that, but my gas mileage is terrible. I've had the car since 1999 and I usually get about 250+ miles on a tank. Now I'm getting 160 miles on a tank. I've had quite a few people suggest replacing the O2 sensors, plugs & wires, air filter. I bought the car new in 99. I've got 40,000 miles on it and I don't drive it in the winter.

bczee

iTrader: (12)

Get the car tuned up (plug, wire, filter, Oil change, etc).. then have someone scan the car/engine to make sure that all of the sensor and reading are within the spec's.

Many have recommened Seafoam'ing the car.. see the maintance section for the sticky.