Wideband O2 Sensors

[Whisky_Tango]

If given enough vapor space and the charge is so high (if not grounded), it will strike to the nearest ground area. When this happens, its like a lightning bolt.

Is it easy to ensure that it is grounded?

Charging of the liquid when it flows along walls (pipes, pumps), when collides with fixed parts or with liquid surfaces, when it is sprayed or when it passes through filters, especially micro filters (pore size < 10micrometer). The pipeline must be completely filled to exclude the possibility of explosible mixture formation with the pipe. Keep the liquid pure. Particles of dust or droplets of water are charge carriers. Velocities must be kept low. For mineral oil products (eg. gsoline, kerosene, paraffin, jet fuel) and other chargeable liquids (excluding carbon disulfide and ether), depending on pipeline size.

Norminal pipe diameter of <40mm, safe max. velocity allowed is 7m/s with max flowrate of 600Litres/min.

To conduct away the positive charge, use conductive hoses or tubes. Where hoses made of non-conductive material with embedded fine wire mesh, the mesh must be connected conductively to the metal flanges or couplings.

The tank containing this liquid must be grounded as well. As the car turns at corners, the liquid will be agitated thus create charges. Higher agitation = higher charge until so great that it will punture thru whatever its in the way.

I have seen this in my customer's plant. Very nice, like fire works.

Wah.. I don't want to die in a burst of fireworks and fuel leh

Static buildup is more to a science thing, there are specialists to troubleshoot this kind of phenomena.

 

[Racebred]

wah eric you are more and more hiong in your chim knowledge.

so in other words, better just go and buy a wideband one lah...shit i thought can save money buy defi one.

 

[Whisky_Tango]

wah eric you are more and more hiong in your chim knowledge.

so in other words, better just go and buy a wideband one lah...shit i thought can save money buy defi one.

No lah... some of it I found in website. Only the static buildup I know cause I have been trying to solve my customer's problem. Hahahha... trying to reply Shuan per his question but dunno how to re-arrange the "quote" until all mixed up.

Might as well buy the wideband since its 100 -200 hundreds more than Delphi. Gives you exact reading.

 

[Crufty Dusty]

Wideband measures often from 10-20:1. Narrowband only is accurate around 13-15:1 or something like that. Very roughly. The exact specifics I don't recall right now but I am sure I am close on the numbers.

Yes, there are 2 main reasons why you need a wideband for tuning.

1) Response time. A good wideband O2 will respond very quickly to changes in AFR. Which is critical for taking measures in preventing engine damage.

2) Accuracy. If you compare the graphs of a wideband and a narrowband O2 sensor, the narrowband as its namesake suggests is only accurate around those numbers you mentioned. Under WOT, it's totally useless.

 

[Racebred]

ok... further hammering home of me should be getting wideband instead of narrow band arguments..

now.... should i take into account what sort of headers to get when i am sourcing for wideband? when i change headers i am still gonna keep my original o2 sensor there right?

 

[Shaun]

no you can custom fit the O2S bung anywhere you want, so no problem

 

[Shaun]

Yes, there are 2 main reasons why you need a wideband for tuning.

1) Response time. A good wideband O2 will respond very quickly to changes in AFR. Which is critical for taking measures in preventing engine damage.

2) Accuracy. If you compare the graphs of a wideband and a narrowband O2 sensor, the narrowband as its namesake suggests is only accurate around those numbers you mentioned. Under WOT, it's totally useless.

I believe 2 is the dominant factor because the tuner is inching up on AFR, approaching from the safe (rich) side. There aren't going to be any sudden transients. And like you say in the rpm and load ranges where damage occurs the quickest, the ecu is not looking at the o2s anyway.

Under WOT yes useless for ecu control of AFR, but useful for the tuner to see where AFR is. I wouldn't call it totally useless.

 

[Crufty Dusty]

Under WOT yes useless for ecu control of AFR, but useful for the tuner to see where AFR is. I wouldn't call it totally useless.

In the case of the narrowband, it can only reveal whether the engine is running rich or lean. It lacks any kind of resolution to see exactly how rich/lean. IMO that qualifies as being totally useless.

An inexperienced tuner relying on a narrowband or closed-loop tuning might commit the following mistake: if the engine is running rich and in an ignition misfire situation, the O2 sensor will show that the car is running lean. Thus he makes a wrong diagnosis and richens the mixture further, thereby aggravating things. Note that this problem wouldn't arise if the tuner is using a working wideband O2 and was paying attention to where the AFR was (which as we established earlier, a narrowband is incapable of doing).

 

[Shaun]

i had mis-speed-read and thought the original statement of "totally useless" was referring to wideband at WOT.

the narrowband is definitely useless at WOT.