Heated o2 Sensor

[87Turbo-TWE4]

I currently run the Delco GNX o2 sensor in my car and wanted to know if there are any benefits to using a heated one.

 

[turbo nasty]

Single wire O2 sensors will cool off at idle or light throttle hampering readings or sometimes jump out of closed loop. Also single wires will foul faster with leaded fuel, etc

Heated 02 sensors will warm up faster, stay heated and last longer in race fuel, etc

Thats why they dont use single wire 02's in the OEM anymore

 

[Razor]

Open/closed loop is controlled by coolant temp on the Buick. And by parameters setup in the chip. That is why some chips are open loop at idle.. no matter the temp or O2.

Single wire O2's are fine for our applications. All sensors foul with leaded fuel.

Stay away from the Bosch sensors on our apps.

Car in theory will run better with a heated O2. In reality, no difference.

HTH

 

[GNVenom]

With a non-heated sensor and a stock exhaust, you won't see a problem with sensor cooling. However, if you have modified your exhaust to flow significantly better than the stock system, the sensor cooling will equate to poor gas mileage. Your MPG will suffer.

When the sensor cools below 900 deg F, the millivolt output falls off, which causes your ECM to add fuel as it "thinks" you are running lean. Your ECM causes a rich condition until the data from the sensor is corrected.

With a heated sensor, that won't happen. The extra heat generated in the sensor tip keeps the sensor above 900 deg F which is where the normal sensing function begins. The sensor has to be very hot to work properly.

Because the OEM's are required to maintain CAFE fuel levels, the heated sensors become standard issue, in fact, they have been doing it since around 1994.

 

[Razor]

With a non-heated sensor and a stock exhaust, you won't see a problem with sensor cooling. However, if you have modified your exhaust to flow significantly better than the stock system, the sensor cooling will equate to poor gas mileage. Your MPG will suffer.

When the sensor cools below 900 deg F, the millivolt output falls off, which causes your ECM to add fuel as it "thinks" you are running lean. Your ECM causes a rich condition until the data from the sensor is corrected.

With a heated sensor, that won't happen. The extra heat generated in the sensor tip keeps the sensor above 900 deg F which is where the normal sensing function begins. The sensor has to be very hot to work properly.

Because the OEM's are required to maintain CAFE fuel levels, the heated sensors become standard issue, in fact, they have been doing it since around 1994.

This is understood like on a 1991 Camaro with a V6.
But..
How does this apply to the 1987 turbo charged 3.8 Buick motor with an O2 sensor sitting before a turbo under a lot of heat?

So your saying switching to a heated O2 sensor on a GN will improve gas mileage over a working single wire O2 sensor? If so by how much?

 

[davidf]

Ok let me ask this since we're on the subject. I have Caspers heated 02 but have yet to install. My Champ. intake deletes the EGR. Looks like the 02 is gonna be plugged into the EGR sensor which I have removed. Do I reinstall the sensor for this? Thanks

 

[TurboDave]

This is understood like on a 1991 Camaro with a V6.
But..
How does this apply to the 1987 turbo charged 3.8 Buick motor with an O2 sensor sitting before a turbo under a lot of heat?

So your saying switching to a heated O2 sensor on a GN will improve gas mileage over a working single wire O2 sensor? If so by how much?

Even sitting pre turbo, that position can and does cool down quite a bit especially during periods of idle condition, or other very light load scenarios.
I have an EGT right there next to the stock O2 (I run a heated AFS74 BTW), and can attest to the fact that temps right there can easilly dip into the mid 700 range at idle.
Yes I run an aftermarket downpipe, and ATR 2.5" exhaust with Magnaflows so it's all pretty free flowing.

 

[GNVenom]

What Dave said. The turbo heats up as you increase boost, but at idle, it's pretty much cool as a cucumber - by comparison.

Also, the heated O2 kit plugs into the EGR connector, only to tap the 12 volt positive and negative feed for the sensor. You don't need the EGR valve attached to the other end to get that power feed to the sensor.

 

[davidf]

Thanks.:smile:

 

[Razor]

Most of the aftermarket chips run open loop for idle anyways. And cruising I see 1100-1200 preturbo on egt. So anytime there is any throttle it goes over 900.

So I guess if you run a closed loop chip at idle you may see an improvement.

Dont know bout cool as a cucumber.. have replaced those sensors on a hot motor not running and they are no fun

 

[turbo nasty]

Bob Bailey is the one that explained the O2 sensor cooling off due to aftermarket headers/higherflowing exh contributing to this.

First discovered it when I set my chip for closed loop idle while adjusting different parameters in teh EXT G and tuning the low load on the GEN2 at idle and saw the BLM's get weird. Scrolled through and noticed it had jumped into open loop.

Im ordering a caspers heated O2 kit to stop this.

 

[we4Mateo]

With the TT chip running open loop idle, I feel my heated O2 makes the car idle better. On the highway, I'm sure it's the same as before but the heated do take partially leaded gas better than non-heated, but I'm switching to no-lead 104 for my needs now.

 

[bmackinnon]

With the TT chip running open loop idle, I feel my heated O2 makes the car idle better. On the highway, I'm sure it's the same as before but the heated do take partially leaded gas better than non-heated, but I'm switching to no-lead 104 for my needs now.

oops... n/m... doh!