CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.

O2 sensor upgrade

opfor2

1/2 ton status
Joined
Oct 28, 2002
Posts
375
Reaction score
1
Location
Ventura County, CA
I would like to upgrade my one wire non heated O2 sensor to a newer heated three wire O2 sensor. Any suggestions on what type of sensor to use and what to do about the connectors?

Thanks

Dan..
 
GM part number: 25312179; AFS-74 heated oxygen sensor, recommended with headers and the OBD-1 GM setups.

Cheap out on the O2 sensor, you may get one out of the box that won't work.
http://coloradok5.com/forums/showthread.php?t=169665&highlight=heated+o2+sensor

I'd look at "investing" in being able to at least keep it as it comes, with a weatherpack connector. You can get the other end you'll need (probably even from a wrecking yard) you'll just have to get the connector pins/seals to connect the wires on the truck side.
 
dyeager535 said:
GM part number: 25312179; AFS-74 heated oxygen sensor, recommended with headers and the OBD-1 GM setups.

I'd look at "investing" in being able to at least keep it as it comes, with a weatherpack connector. You can get the other end you'll need (probably even from a wrecking yard) you'll just have to get the connector pins/seals to connect the wires on the truck side.

I want to do it correctly by using the proper weatherpack connector. Do you know if the connector with a short wire lead is available from GM or maybe NAPA ??

Dan..
 
opfor2 said:
I want to do it correctly by using the proper weatherpack connector. Do you know if the connector with a short wire lead is available from GM or maybe NAPA ??

Dan..

Update:

The NAPA O2 sensor connector #ECHEC162 does not fit the AFS-74 O2 sensor connector..

I found the answer to my own question. NAPA Oxygen sensor connector NAPA PN ECHEC162 $ 22.99 This fits the three wire O2 sensor AFS-74. I'm looking forward on completing this mod. Hopefully it will make my truck run better. I installed a set of Edelbrock headers and I'm thinking that the one wire O2 sensor just doesn't get hot enough to make the truck go into "closed loop" fast enough..
 
Last edited:
I have to ask....What is the "closed loop"?

I just put on a pair of Doug Th. headers on my 88 454 sub. My idiot light has been on coding 44 "lean". I wounder if it is related.

I put a new 1 wire o2 sensor in to try and solve the problem. Funny, light comes on at a different time. Now it comes on almost exactly 15 minutes of highway speed. Right about the time engine heat gets to 200.

Hobbs
 
Closed loop is when the ECM is using the data from the O2 sensor to regulate the air/fuel mixture. One problem with using headers is that the exhaust gas does not make the o2 sensor hot enough so the ECM stays in open loop and the air / fuel mixture is not regulated. One way to fix that problem is by upgrading the O2 sensor from a single wire unheated to a three wire heated sensor. A simple fix.


Hobbs said:
I have to ask....What is the "closed loop"?

I just put on a pair of Doug Th. headers on my 88 454 sub. My idiot light has been on coding 44 "lean". I wounder if it is related.

I put a new 1 wire o2 sensor in to try and solve the problem. Funny, light comes on at a different time. Now it comes on almost exactly 15 minutes of highway speed. Right about the time engine heat gets to 200.

Hobbs
 
You can get a bare weatherpack: NAPA BEL 725177-376 and the pins for 5.00 if you don't mind making your own.
 
opfor2 said:
Do you know if the connector with a short wire lead is available from GM or maybe NAPA ??

Dan..

Yes it is. I bought one. Gm part number 12126012. Looks to be the same ones used for TPS and other 3 wired OEM stuff. Comes with about a foot of lead wire.
 
randy88k5 said:
Yes it is. I bought one. Gm part number 12126012. Looks to be the same ones used for TPS and other 3 wired OEM stuff. Comes with about a foot of lead wire.


Are you sure that that's the correct AC Delco part number? When I searched for it on ACDELCO.com it came up as an invalid part number. Maybe this part number is a GM only number??

Thanks

Dan..
 

Latest Posts

Top Bottom