1995 Silverado Oxygen Sensor Oddity

[zhaarnak02]

Greetings to all of you. I am an old "Gearhead" that has been "Lurking" here for some time, and I have come across an oddity that I hope one of you fellow Gearheads may be able to shed some light on. It involves a friends 1995 Silverado, 5.7, 4L60E with that had been running a "tad" oddly. They replaced a few items which included (among the normal items, plugs and wires) the EGR valve, PCV valve, and Oxygen sensor. I road tested the rig first thing, and although she was not missing, she felt a bit odd. During whenever I work on a rig that has had certain "New Brand Name Parts" installed and no longer runs right, I take a look at the "Brand Name" parts for counterfit reasons. The new oxygen sensor is a Denso 3-wire, upstream sensor with the following markings: 1st line, DENSO. 2nd line: ASSEMBLED. 3rd line: IN USA. 4th line: 234000-5530. 5th line: 05E03. Now, what I find odd is I cannot find this number in the online DENSO catalog, nor do I find this beast ANYWHERE online, and this is even if I drop the zeros in the first series of numbers as it appears that this is how DENSO is now assigning numbers.

Can any of you shed some light on this oddity? I have been scratching my head and I would really prefer to retain what little hair I have left. Thanks! and have a great Christmas and New Years!!!

 

[KGMtech]

Contact Denso directly, they should be able to tell you if there is any concern about the part being fake.

 

[slacktide_bitog]

The Denso part number seems to be 234-3011

I think 05E03 is the date code or something, and that 234000-5530 appears in the stock images
(the stock image pictures a sensor made in Japan, but Denso could use both countries to make them)

But if you think it's fake, contact Denso, and they can verify

 

[KGMtech]

And, Welcome to BITOG !! hope you visit with other questions or oil related information.

 

[zhaarnak02]

Thanks for the replies. What got me interested was the fact that I went through more than a few adjacent years of this truck and did not see this O2 sensor listed anywhere. And then when I performed a search on yea olde "DARPANET" the sensor failed to show up as well. I certainly will NOT be putting this thing back in it's hole. Time to head to NAPA. (Hades, this thing could be for a Trabby for all I know!

Best wishes for you all. Keep yer rotating devices in their proper orientation!!

 

[D60]

FYI, as you approach the GMT800 breakover (circa '99) the term "Silverado" will screw you on parts listings. GMT400 is usually just K1500, K2500 etc, while GMT800 is Silverado.

Useless trivia that may be useful one day

 

[SC Maintenance]

Is it OBD 1 or OBD2?

OBD2 was mandated in 1996 but sometimes vehicles got them early. If its OBD2 you should be able to look at your long term fuel trims - which might tell you if its a fuel / 02 sensor issue - before you fire the parts canon?

 

[iCurious]

Is it OBD 1 or OBD2?

OBD2 was mandated in 1996 but sometimes vehicles got them early. If its OBD2 you should be able to look at your long term fuel trims - which might tell you if its a fuel / 02 sensor issue - before you fire the parts canon?

It's definitely OBD 1 on this truck. Live data is also available but requires a dedicated scan tool.

 

[zhaarnak02]

Yep, OBD 1. I just found it odd that the part number does not seem to exist. Heh, appears that 1-wire O2 sensors are pretty much "stone age" now. kind of like me ;-). Why, in MY day the only tool we had was a rock. (it had MANY uses)

 

[michaelluscher]

Here's the single wire you need
Aka ACDelco AFS21
https://www.finditparts.com/products/1431774/ac-delco-afs21?ga_list=Search Results v3
There's some NOS units on eBay, if you're not in a hurry
Do you have/want an OBD1 scan tool for viewing live data?

 

[slacktide_bitog]

Here's the single wire you need
Aka ACDelco AFS21
https://www.finditparts.com/products/1431774/ac-delco-afs21?ga_list=Search Results v3
There's some NOS units on eBay, if you're not in a hurry
Do you have/want an OBD1 scan tool for viewing live data?
View attachment 315425
View attachment 315427

Yep, OBD 1. I just found it odd that the part number does not seem to exist. Heh, appears that 1-wire O2 sensors are pretty much "stone age" now. kind of like me ;-). Why, in MY day the only tool we had was a rock. (it had MANY uses)

Get the 1-wire NTK sensor

 

[clinebarger]

You can run a 3 wire heated oxygen sensor by running a Fused Ignition Hot & a Ground......Assuming it's not a 3 wire heated sensor from the factory already. I've seen '94 & '95 TBI GMT400 trucks have 3 wire sensors heated or 1 wire non-heated sensors.

3 wire sensor is Delco part# AFS76, Or GM part# 19178938.

1 wire to 3 wire Adaptor harness if needed....HERE

1 wire sensor if that's what you have & don't want to convert, GM part# 25166816

 

[zhaarnak02]

Thank you for your research michaelluscher! He decided that his old girl is going to get updated to a 3-wire (heated) when I informed him that my was my 93 was getting updated too, just as clinebarger has detailed. It is nice that the GM engineers thoughtfully placed "dimples" in the firewall so that a couple more oem relays would fit behind the plastic cover! The install on my old girl will be in the original location, but will be moved the junction of the "Y" pipe when my exhaust system gets replaced. Hopefully BEFORE it parts company with the truck and introduces itself to a late model AUDI following me too closely :O

 

[zhaarnak02]

"Well, officer, in MY defense, he WAS following me just a TAD too closely. Can you just charge me for littering and having a unsecured load"? HEH, old age and treachery defeats youth and enthusiasm all the time, and I and my rig are old, old, old.

 

[4wd]

"Well, officer, in MY defense, he WAS following me just a TAD too closely. Can you just charge me for littering and having an unsecured load"? HEH, old age and treachery defeats youth and enthusiasm all the time, and I and my rig are old, old, old.

Saw an old buddy yesterday - on the back of his Chevy truck:
“I’m sorry for driving so close to you - while in front of you”

 

[zhaarnak02]

Funny story. A few years ago I had a discussion with an retired pipe fitter about drivers following entirely to close. He told me how he would "dissuade" that type of behavior when he was driving his work truck. He welded a very large pipe wrench to his rear bumper in a position that "looked" like it was about to fall off the truck. He told me that he would get a hoot watching the person start riding his a$$ and then notice the pipe wrench. He also said that he wished he had installed a rear camera to record the reaction. He did say that at times they would pull up alongside and attempt to get his attention. I also think I will have that bumper sticker made for my truck. Thanks 4WD!

 

[LDM]

You can run a 3 wire heated oxygen sensor by running a Fused Ignition Hot & a Ground......Assuming it's not a 3 wire heated sensor from the factory already. I've seen '94 & '95 TBI GMT400 trucks have 3 wire sensors heated or 1 wire non-heated sensors.

3 wire sensor is Delco part# AFS76, Or GM part# 19178938.

1 wire to 3 wire Adaptor harness if needed....HERE

1 wire sensor if that's what you have & don't want to convert, GM part# 25166816

Its funny how they didn't bother to standardize the O2 sensors on these trucks until OBD2 came along. My 95 Tahoe had the 3 wire setup yet you can go find another truck from the same year and it has the 1 wire for whatever reason. Yet the 94-95 LT1 cars all have 4 wire O2 sensors.

I would recommend upgrading to the 3 wire as it works much better than the old 1 wire non-heater O2 sensors. I did this on my 89 Camaro to improve keeping the ECM in closed loop, the exhaust didn't always keep the O2 sensor hot enough and it would drop between open and closed loop while driving. Annoying when trying to tune it for improved power and response.

 

[zhaarnak02]

Ordered the sensor and new connector yesterday, and going to mount the (GM) relay and start fabricating the harness tday. (If it aint a blizzard anyway)........ (I probably just sent a RSVP to good old "Murphy" didnt I) SIGH, when will I ever learn...

 

[LDM]

Ordered the sensor and new connector yesterday, and going to mount the (GM) relay and start fabricating the harness tday. (If it aint a blizzard anyway)........ (I probably just sent a RSVP to good old "Murphy" didnt I) SIGH, when will I ever learn...

Yes. I waited to do the fluid film on mine and my brothers trucks because we really don't get much in the way of snow here in IL in Dec anymore. Well that was wrong this year to say the least. I got both trucks oil changed and the fluid film applied this morning as all the snow is gone and it was warm enough to take them to the car wash and get all the salt of them both. I should have known better than to put it off but what was a couple more days? Over a foot of snow in the end.

 

[zhaarnak02]

I came to the conclusion, a long time ago, that Murphy and Mother Nature are easily bored individuals and being so, really get excited when one of us stupidly thinks or says "the weather will hold for a bit longer", "how bad can it get", or that most egregious of thoughts, "Meh, I"ve seen worse, show me what you've got". THAT one is when Murphy says "hold ma beer" and Mother Nature says "hold my wine"
Anyone here old enough to remember the old butter commercial where she is more than a little irritated about fake butter (Chiffon)?