I am FINALLY getting my ProCharger installed this week! My tuner asked me to find out if there is a 'clamp on' bung for the wideband sensor. He said he has seen one, where you drill a hole in your pipe, then use a bung that is built into a special clamp to secure it to your pipe.

Does anyone know what this is?

Where can I get one?

Is it any good?

 

No, they are highly prone to leaks which is a huge issue when you start tuning with it. Your best bet is to get a bung welded into the pipe.

 

I have my wideband mounted where the rear 02 sensors would have been.

 

Your supposed to put it before the cat correct?

 

^^^^^^


Correct

 

Sorry, but a tuner that suggests a clamp on bung like you mentioned, scares the sh*t out of me.

That's all I would have to hear and I'd be going to someone else - quick.

Just opinion, it's your car, but I wouldn't feel right not to say something.

 

I went ahead and ordered a stainless bung from Summit Racing this morning. I will have it welded before my hi-flow cats on Friday.

The guy is not really a true tuner. He is just installing the Pro Charger for me, wiht my supervision.

 

The wide band needs to be as close as possible to the collector or manifold to give the best readings. I would not put it to close to the cats for fear of the heat affecting life span.

 

Installed one in my MN6 here:

http://redshift.homestead.com/WBO2.html

And here's the bug I had welded in the AR header X-pipe in the wife's A4.

 

my tuner also put mine in one of the bungs where the rear 02 would of gone. This is behind my cats. I was going to say something, but he said he didn't want to go through all that hassle putting a bung in when it really didn't matter. So what is the truth, I had heard it from lots of people. Whats from a tuners point of view? Also is it that hard to weld a bung in if the system is already on the car? Right now I have been getting readings that are jumping all around. I am wondering if this might be why.

 

It is natural for the readings to jump until you're WOT. Then they should be fairly stable. In closed loop, the computer pulses fuel to make the engine go constantly rich/lean on purpose.

 

if you dont have any cats.... does it matter if it goes in one of the rear o2 bungs?

 

Installing a wideband 02 after the cats will skew your readings. Just how much, I don't know. The sole purpose of the rear oxygen sensors in a normal setup is to monitor the condition of the cats. They do this by monitoring the 02 level in the exhaust. When the exhaust passes across the catalyst in the cats, the nitrogen oxides are changed into nitrogen and oxygen, some of this oxygen is then used to combine with the carbon monoxide (CO) to produce carbon dioxide (CO2). Not all of the oxygen is used, so the exhaust after the cats has a higher oxygen content than the exhaust before the cats. This is how the PCM monitors the cats. If the rear oxygen sensors are reading a higher 02 content than the fronts, then the PCM knows that the cats are working properly. So, putting the wideband after the cats will produce a leaner reading.

The same is true for putting the wideband sensor in the tailpipe. A not-so-well-known solution to eliminating the CEL when a cat is removed from a car, is to weld a bung in the exhaust at the very end of the tailpipe, extend the wires and put the rear 02 in it. There is enough difference in the oxygen content that the CEL won't illuminate. (Don't tell anyone I told you this.)

Clif, the setup that Patches has is probably the best setup, since it reads the exhaust from both side of the motor. If your guy doesn't want to weld a bung in, the best thing to do is to use a wideband controller that will simulate a narrowband 02. This way you just remove one of your stock front narrowband 02s and replace it with the wideband 02. Follow the manufacturers directions on how to wire it.

If you are going to mount the wideband in the car permanently and plan on using HP Tuners, there is a good write up here that lets you read the wideband directly through the OBDII connector.

 

Thanks for all the advice! I got my bung in from Summit the very next day! Yesday was the 4rth, so no shop was open; so today I am getting it welded in similar to Patches setup.

The install is going slow. It took six hours to move the steering rack and remove the balancer bolt for pinning. That is as far as we got yesterday.

 

From what I've read, and it seems logical to me, the bung should be welded into the pipe in the +9 o'clock to -3 o'clock position, if the wideband sensor is going to be permanently installed.
If the sensor is mounted in the + 3 o'clock to - 9 o'clock postion, condensation and comtaminants can collect in the tip of the sensor.
If you are going to use the wideband sensor for dynotuning or short term street tuning, the bung can be positioned for ease of installation. Just be sure if you hit a bump in the road, your not going to rip the sensor out of the pipe.