best o2 sensors??

[redbird555]

my car was an 02 and I experienced similiar problems wot the poster above. I could watch the bosch o2's on my car switch very slowly compared to the densos and sometimes the sensor would just 0 out and the car would throw p0151 codes. Since I switched to densos everything has been fine... IMO if gm puts densos in their cars today there cant be anything really wrong with the brand. Bosch o2's work fine for some and others have issues just my 02. Btw to the guy above it sounds like you may have another bad sensor idk what would make the computer throw that code. I suppose it could be a dirty maf causing a "lean" condition on that side then having it dump a crapload of fuel into the motor thus fouling the o2 but its not likely.

[pajeff02]

Any pics of the installed sensors? Curious if the angle may be the issue. The tip of the sensor that goes into the exhaust should point downward. Some are parallel to the ground, which is also okay, but a downward angle is best as it prevents moisture from accumulating on the sensor during short run cycles.

[My00Z28]

well just ran out side and put the rear on ramps and it looks like im kinda screwed on the angle thing!

[pajeff02]

That could be at least part, if not all, of your problem right there. FWIW, you can buy bung kits from Jegs and Summit along with a set of plugs. This would allow you to relocate the senders. Are they early OBX headers?

[My00Z28]

ebay headers... most of the time when i get problems is when i do long drives or last time it did it was when i was racing and driving back home still along drive

[Firebirdjones]

I'm with Jeff, and tend to believe you don't have a sensor issue, it's the installed angle.

These things HATE moisture and should always be at least parrallel to the ground, but ideal would be angled downward at a 1 or 2 o'clock position if you have the room.
Frankly, that thing looks like it hangs so low it might catch on something. It's an easy fix though. Plug that bung off and drill a new hole in a better position, weld another bung in and you're golden.

[Firebirdjones]

my car was an 02 and I experienced similiar problems wot the poster above. I could watch the bosch o2's on my car switch very slowly compared to the densos and sometimes the sensor would just 0 out and the car would throw p0151 codes. Since I switched to densos everything has been fine... IMO if gm puts densos in their cars today there cant be anything really wrong with the brand. Bosch o2's work fine for some and others have issues just my 02. Btw to the guy above it sounds like you may have another bad sensor idk what would make the computer throw that code. I suppose it could be a dirty maf causing a "lean" condition on that side then having it dump a crapload of fuel into the motor thus fouling the o2 but its not likely.

Nothing wrong with denso's. I've used them before. The cost is about the same between those and Bosch so it's a wash.
The only issue I run into is that GM parts like denso sensors aren't always carried by local parts stores, unless you hit the dealer and pay even more money.
Only place you can get a deal on GM parts would be online, and to be honest, I don't buy electrical parts online, because if there is a problem it's a pain in the ass to warranty or return it.
I'd rather buy electrical parts local, so if there is a problem it's a simple trip to the store and problem solved with little to no down time. Because of that, and the fact that so many have excellent results with bosch, and just about any parts store carries them,,,,that's what I went with.

As a matter of fact, the 6.0 swap I just did in my blazer has GM sensors in it. That's what Howell supplied with the custom harness, and they work just fine. I don't have a problem with using them, I just have a problem finding them local.

[herculesrider1]

A few days ago, I purchased two Denso's...234-4025(pre-cat left $65) and 234-4087(pre-cat right $41) specifically for my '00 T/A. The pigtails for the upstream was maybe 6". WAAAAY to short. I would have had to splice, extend, re-wire etc. and that is nothing but a pain. Jeff recommended the Bosch 13111's, so, I looked up the sensor in a technical write up and it gave the switching frequencies, etc, and the harness length.....ready?....51 inches from sensor to connector. And the connector will attach to the existing factory connector without the need for splicing, extending or re-wiring. I found the Bosch 13111's on eBay for $39each and will get them in 4 days free shipping. Can't beat a deal like that for brand new, still in the package sensors. I love this site!!!

[My00Z28]

I'm with Jeff, and tend to believe you don't have a sensor issue, it's the installed angle.

These things HATE moisture and should always be at least parrallel to the ground, but ideal would be angled downward at a 1 or 2 o'clock position if you have the room.
Frankly, that thing looks like it hangs so low it might catch on something. It's an easy fix though. Plug that bung off and drill a new hole in a better position, weld another bung in and you're golden.

Well this just notified me again! Back from the dead! But I got my problem sorted out kinda? Idk what my problem was with them but I did new plugs and wires again then replaced both o2 sensors as a pair.... Problem solved!

[herculesrider1]

Well this just notified me again! Back from the dead! But I got my problem sorted out kinda? Idk what my problem was with them but I did new plugs and wires again then replaced both o2 sensors as a pair.... Problem solved!

Yeah Kyle, I just replaced my plugs and wires too, and as soon as my 13111's come in the mail, I'll be replacing both of my O2 sensors too. I should have the same results....a solved problem.

[herculesrider1]

Installed the Bosch 13111's, had plenty of wiring lead so that I didn't have to splice. Now she runs great, just like she did before, and my gas mileage has drastically gone up. It got as low as 12mpg. Now with the new O2 sensors it's back up to 21mpg around town. I would like to thank everyone for their input along this journey and for helping me locate my problem. I love this site. Problem solved!!!

[BigFrog]

I am looking for part numbers to replace all 4 O2 Sensors in my 2002 SS. I am having both original factory cats replaced with Flowmaster cats. I want to make sure everything is buttoned up nice in one visit to the muffler man.

I keep seeing mention of using Corvette sensors (Bosch 13111) which can me had for $40 each. Can I use those in all four locations? If not, what should I get for the other pair?

THANKS IN ADVANCE

[SMWS6TA]

Most ppl that get the 13111's is because they have installed long tube headers and have deleted or moved the CATS so they do not have to use extension harness to make the stock ones work.

If you are still under stock exhaust just get the OEM replacement. I prefer Bosch O2 sensors.

[pajeff02]

The rear O2 senders simply tell the PCM if the cats are working. They in no way affect how the engine fuels or runs. Honestly, I would not swap them out until they actually go bad. Why waste the $$? Most guys have them tuned out anymore and plug the holes.

[BigFrog]

The problem I am having is I find posts all over that say "all four are the same" or "all four are almost the same" and I see part numbers for one pair or the other, but nothing that shows part numbers for all four. When I look them up on auto part sites there are either just 1 or 2 on the fitment chart, or there are a dozen, some labeled "upstream" and "downstream" and some labelled "front" and "rear" as well as left and right and driver and passenger. I just want to order all four (or even the front pair only) and know I am getting the right ones the first time without having to exchange them

[SMWS6TA]

1 and upstream are for before the CATS, 2 and downstream are after the CATS.

What place are you ordering or pricing from?

[pajeff02]

I would definitely install Bosch P/N 13111 O2 senders in the upstream (pre-cat) location. If the extra length of the harness is going to be an issue, then these are the correct part numbers for upstream and downstream senders:

UPSTREAM: Bosch P/N 13444

DOWNSTREAM: Bosch P/N 13444 (Alt. P/N 13029 will also work, but is more expensive)

You will need a special socket to change the sensors so as not to damage the wire harness.