ViribusUnits - 3 wire O2 sensor?
09-27-2003, 10:30 PM
#1
Intermediate
Thread Starter
Join Date: Jul 2003
Location: Nashotah, Wisconsin
Posts: 41
Likes: 0
Received 0 Likes
on
0 Posts
ViribusUnits - 3 wire O2 sensor?
In a recent post re : 83 exhaust systems Viribus wrote he retards timing and uses a 3 wire O2 sensor to pass the sniffer test. Is there an alternate to the 3 wire sensor on an '83?
09-27-2003, 11:30 PM
#2
Nordschleife Master
John, what you do to pass the sniffer test depends on your car. Exactly what the regs are and what it fails under are up to your car. Exactly what has been done to you car also depends on what you have to do. Rember, adjusting it one way, and then adjusting it back another is not strictly legal, nor is it very enviromentaly freindly.
For the first thing, I haven't yet been required to take the sniffer test, I suspect with the way things are right now I'll pass it, as I've done some testing you see, but I've never had to legaly do it.
Rember though, there is the 3 wire universal sensor. It's Bosch part number is 13913, and it's worth 50 buck to your local autozone. The single wire is a possible option, it's Bosch part number is 11027, and it's worth about 22 buck to your local auto zone. To replace it with a universal, you have to snip the wires to the old sensor, ans then crimp on the new sensor. It's not as clean as the correct sensor, but apperently works just fine.
What are the modifications, if any, to your car. I might be able to help point you in the right diriction. Have you failed a sniffer test?
Good luck.
For the first thing, I haven't yet been required to take the sniffer test, I suspect with the way things are right now I'll pass it, as I've done some testing you see, but I've never had to legaly do it.
Rember though, there is the 3 wire universal sensor. It's Bosch part number is 13913, and it's worth 50 buck to your local autozone. The single wire is a possible option, it's Bosch part number is 11027, and it's worth about 22 buck to your local auto zone. To replace it with a universal, you have to snip the wires to the old sensor, ans then crimp on the new sensor. It's not as clean as the correct sensor, but apperently works just fine.
What are the modifications, if any, to your car. I might be able to help point you in the right diriction. Have you failed a sniffer test?
Good luck.
09-28-2003, 01:25 AM
#3
Intermediate
Thread Starter
Join Date: Jul 2003
Location: Nashotah, Wisconsin
Posts: 41
Likes: 0
Received 0 Likes
on
0 Posts
Thanks VU, No Mods and dont have to test.... Was interested in the inverse of detuning. Thanks very much for the detailed info. Stripped threads on my three wire I'll give the 22 dollar unit a shot.
09-28-2003, 01:41 AM
#4
Nordschleife Master
The inverse of detuneing?
You sound like a man trying to eighter retune you car, OR get back some of the proformance the EPA made Porsche take away?
Anyways, if you have an option, go for the 3 wire unit. The extra two wires, and $30 are for a heating element. This will bring your car into tune on start up much quicker than the single wire unit. It will also make sure that the O2 sensor functions even dureing extended idleing. The single wire sensor doesn't have a heater, and is dependent on the hot exaust gases to keep it in opperating temp. As it cools, it defaults to indecateing a lean mix, resulting in the computer trying to make it extra rich to compensate. Not the best happening.
If your looking for more power, there is a way to make your AFM read a false high, resulting in a rich mixture. This can allow you to add a few extra degrees of spark advance. I've been told it's good for 20 hp. I'm not sure if I can feel 20 hp or not. This is how I found my car.
Btw, this makes you completely fail just about all emissions testing. HC too high, and NOX too high. Sometimes the O2 sensor will correct for the CO trying to get too high. I belive Porsche ran such a concervitive timeing curve on the 928 not to protect the engine from detonation, but to prevent poor emissions. Just my susspession though.
Good luck.
You sound like a man trying to eighter retune you car, OR get back some of the proformance the EPA made Porsche take away?
Anyways, if you have an option, go for the 3 wire unit. The extra two wires, and $30 are for a heating element. This will bring your car into tune on start up much quicker than the single wire unit. It will also make sure that the O2 sensor functions even dureing extended idleing. The single wire sensor doesn't have a heater, and is dependent on the hot exaust gases to keep it in opperating temp. As it cools, it defaults to indecateing a lean mix, resulting in the computer trying to make it extra rich to compensate. Not the best happening.
If your looking for more power, there is a way to make your AFM read a false high, resulting in a rich mixture. This can allow you to add a few extra degrees of spark advance. I've been told it's good for 20 hp. I'm not sure if I can feel 20 hp or not. This is how I found my car.
Btw, this makes you completely fail just about all emissions testing. HC too high, and NOX too high. Sometimes the O2 sensor will correct for the CO trying to get too high. I belive Porsche ran such a concervitive timeing curve on the 928 not to protect the engine from detonation, but to prevent poor emissions. Just my susspession though.
Good luck.