1 wire to 3 wire O2 Sensor

[rockymtnlover]

I've heard of using a heated 3 wire O2 sensor in place of the 1 wire... any opinions on which one, or what to look for... or will anything they have in stock work since I'll be cutting off the plug and wiring it up anyway.

 

[PlayingWithTBI]

will anything they have in stock work since I'll be cutting off the plug and wiring it up anyway.

You don't need to cut the connector with this setup.

www.amazon.com/ACDelco-AFS74-Original-Equipment-Heated/dp/B000C9VTRC/ref=sr_1_3?dchild=1&keywords=acdelco+afs74&qid=1634063397&sr=8-3

www.amazon.com/Michigan-Motorsports-Heated-Harness-Adapter/dp/B0141VHZ6U/ref=sr_1_1?dchild=1&keywords=michigan+motorsports+22300&qid=1634063344&sr=8-1

 

[rockymtnlover]

Slick, thanks!!

 

[Frank Enstein]

If you have shorty headers or factory manifolds where the O2 sensor is less than 12" from the engine.

The idea of the heated O2 is to get the engine into closed loop or to keep it in closed loop at a long traffic light.

This can be a big help with long tube headers.

 

[PlayingWithTBI]

If you have shorty headers or factory manifolds where the O2 sensor is less than 12" from the engine.

The idea of the heated O2 is to get the engine into closed loop or to keep it in closed loop at a long traffic light.

It helped with my shorty headers too. With a free flowing exhaust i.e. headers, mandrel bent pipes, high flow cat, straight through muffler, you'll get into closed loop sooner and stay in closed loop while idling.

 

[rockymtnlover]

PlayingwithTBI, that's the goal... the truck has short tube headers, mandrel bends, 3" single exhaust, big ass muffler... The current O2 is seized into the driver's side collector. I'm planning on moving it over to the other side just after the Y so it's measuring the average of both sides. Thanks for the parts links!

 

[Nad_Yvalhosert]

PlayingwithTBI, that's the goal... the truck has short tube headers, mandrel bends, 3" single exhaust, big ass muffler... The current O2 is seized into the driver's side collector. I'm planning on moving it over to the other side just after the Y so it's measuring the average of both sides. Thanks for the parts links!

That's the OE location of the 1 wire sensor on my '95 2500 TBI 5.7. Strange to me that it doesnt need a heater circuit...

 

[PlayingWithTBI]

I'm planning on moving it over to the other side just after the Y so it's measuring the average of both sides.

Being that far away from the exhaust ports you may get surging due to response time of the ECM. There is a parameter in the .bin where you can delay the response based on Gms/Sec flow. I'm running a WBO2 in the Y collector and had to delay the response to stop (or at least slow down) that surging. It's worse with a more aggressive cam so, you may be good to go. As usual YMMV

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Here's the explanation for a 1227747 ECM

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[PlayingWithTBI]

That's the OE location of the 1 wire sensor on my '95 2500 TBI 5.7. Strange to me that it doesnt need a heater circuit...

The OE location is in the collector of the "Y" pipe and not the cast iron exhaust manifold on the driver's side?

 

[Nad_Yvalhosert]

The OE location is in the collector of the "Y" pipe and not the cast iron exhaust manifold on the driver's side?

On mine, yes. The exhaust manifold has the flat section where the bung would be drilled and threaded. But its solid and original.
The OE y-pipe has the bung, right at the Y on the passenger side, and the 1 -wire pigtail comes right out the the harness & shield that holds the wires to the starter.
And both my '88 GMC and my '89 Chevy, both 1500's, both 4x4's, both 5.7's, have the O2 in the manifold. Not sure when or why GM changed but I've always thought the ECM got better readings (combination of both banks) from the Y, than from only one side...