DynoJet Wideband Commander?

[final5-0]

Alright, I have the Commander installed, but at idle and reving the needle sweeps from 14 to 18 ...bascially all over the place. I called my tuner and he said that he's had a few poeple with the commander and they had problems with it doing funky things. Have any of ya'll with one installed have these problems? Please help!

At idle your O2's do indeed switch back and forth rapidly.
This is a normal thing.
Your wb display is not filtered like a typical dyno display.
IMHO, what you are seeing is normal.

Here is some info based on my findings.

If I look at my display in real time during idle, the digital numbers jump at such a quick rate, I kinda have to average them to arrive at a value.

For the most part, I see the numbers stay in a range of 15 to 16. Every now and then, I do see a value of 1.00 point + or - more than that range pop up.

I run a bit lean at idle as my combo seems to prefer it. I suspect it has to do with my cam specs and LT's.

Grady

 

[final5-0]

I also heard that the airfuel gauge is only uselful at WOT.

This info would seem to be correct ...................
and from a WOT perspective ...............
I guess it is

HOWEVER

I just can't let it go ............ as it stands

because ...... it is misleading to the point that it could be passed on and on and eventually fall into that category I so despise

Internet Myth

Consider something along these lines that may give you more options with your wb or give you a tool that can be used for more applications other than WOT.

If you can output to a laptop ................

Load the data in Excell

It can give you an average of values with ease




I Love It

Internet Myth Debunked

Before it even got a chance to get started ...... maybe

Just one more reason ............ :SNSign: .............#1

Grady

 

[KBCobra95]

Thanks for clearing that up! Dang, I was hoping to get one started

 

[Rootus]

As much as I hate to disagree with Grady...

At idle your O2's do indeed switch back and forth rapidly.
This is a normal thing.

On a narrowband O2 gauge, yes. But the actual mixture change is very small, on the order of 14.5-14.7 -- so seeing a wideband going way above 15.0 in closed loop suggests a problem.

Mine started doing the wild fluctuations once, but not all the time. When I pulled it out of the car to inspect the wiring, it turns out the wires had gotten too close to the exhaust and one melted through the insulation. So in certain situations it would ground itself out and cause the gauge to go nuts.

Your wb display is not filtered like a typical dyno display.
IMHO, what you are seeing is normal.

Not true . The DJWBC has a brain box, and the gauge display is definitely filtered. You can hook a laptop to the brain box and control the smoothing. The stock setting is not heavily smoothed, but it is not the raw sensor output either.

For the most part, I see the numbers stay in a range of 15 to 16. Every now and then, I do see a value of 1.00 point + or - more than that range pop up.

In stable closed loop, you'd better see it bouncing around 14.7, else your wideband is lying to you .

The original poster is not entirely clear on this -- at idle, with no input from the driver, the needle should basically be doing the 14.5-14.7 oscillation. Any input at all from the driver and the wide swings are normal.

Dave

 

[final5-0]

As much as I hate to disagree with Grady...

On a narrowband O2 gauge, yes. But the actual mixture change is very small, on the order of 14.5-14.7 -- so seeing a wideband going way above 15.0 in closed loop suggests a problem.

Mine started doing the wild fluctuations once, but not all the time. When I pulled it out of the car to inspect the wiring, it turns out the wires had gotten too close to the exhaust and one melted through the insulation. So in certain situations it would ground itself out and cause the gauge to go nuts.

Not true . The DJWBC has a brain box, and the gauge display is definitely filtered. You can hook a laptop to the brain box and control the smoothing. The stock setting is not heavily smoothed, but it is not the raw sensor output either.

In stable closed loop, you'd better see it bouncing around 14.7, else your wideband is lying to you .

The original poster is not entirely clear on this -- at idle, with no input from the driver, the needle should basically be doing the 14.5-14.7 oscillation. Any input at all from the driver and the wide swings are normal.

Dave

OK Dave

You make some points that I do indeed believe I need to rethink

As my wb is pretty old tech compared to the units you guys use today. I think it would be best for the members to follow the info Dave has provided here.

I should have thought about the wb technology improving

My wb has always displayed as I stated and at the time I got it, I checked with others and they had similar results. When I average those results I do see things as you would expect.

For all I know ...................
I may not have ANY filtering on my old dinosaur wb

anyway ............

Sorry if I confused anyone
and
thanks to Dave for the CORRECT info

I do use a tune that I have modified to idle in Open Loop but I did not think it was anything that would be helpful or applicable here.

Most Important Thing To Me Is This ........................

If ANYONE ever sees something I have posted that they believe to be in error as this instance has turned out to be ...................

Please do as Dave has done and lets not allow info that is wrong to be passed on and on

Once again, I didn't mean to lead anyone down the wrong path

Grady

 

[KBCobra95]

TTT on the wich wire is the switch (non power) side of the ignition coil?

 

[Rootus]

TTT on the wich wire is the switch (non power) side of the ignition coil?

For tach pickup? If you can locate a wiring harness diagram for the 94/95 EEC, you can tap the wire behind the kick panel, right before it reaches the connector for the EEC. That's what I did on my '03 Cobra, and it worked very well. Saves having to go through the firewall.

Dave

 

[final5-0]

I thought a good bit this afternoon about the stuff I posted above and the things Dave pointed out as well.

I did have these thoughts about the two different wide band outputs.

There is one output to the normal visual display.

There is another output which is analog. One would use this to input another device such as I have done with my Tweecer.

I had thought for a while, one might be more filtered than the other
HOWEVER
I've had both outputs displayed simultaneously with my old FJO and they both seemed to look the same and jump around the same amount.

Guess at this time, I still have questions that are unanswered as to why my and KBCobra95's values at idle swing more than Dave's.

Grady

 

[SWYZ721]

Don't WBs take a certain amount of time to "heat up" before reading accurately?

Also could you take your car to a tuner and see what kind of AF ration tehy get? Then, compare and contrast.

Also, is their an optimal distance from the heads that a WB should be? If so, then why do some shops have place the WBs in the tail-pipe?

Also do not the stock 02s swing back and forth rapidly, if using his WB in place of the stock 02 cause this to happen?

 

[final5-0]

Don't WBs take a certain amount of time to "heat up" before reading accurately?

Mine does. It shows no activity until normal temps.

Also could you take your car to a tuner and see what kind of AF ration tehy get? Then, compare and contrast.

Sure you could. Since the focus of activity while at the dyno is WOT.You usually don't idle a lot to keep temps down for your WOT pull.

Also, is their an optimal distance from the heads that a WB should be? If so, then why do some shops have place the WBs in the tail-pipe?

Some dyno places use a sniffer WB. Just a different type ... thats all.

I do run cats and I've had several peeps tell me that a sniffer WB behind cats will read leaner than a WB before the cats.

Also do not the stock 02s swing back and forth rapidly, if using his WB in place of the stock 02 cause this to happen?

Yes, the narrow band O2's do have a lot of activity during idle.

For my setup, I have a bung in each header that allows me to take readings from either side which means my WB is stand alone from my oem narrow band O2's.

Some of the newer WB's can be used to replace one of the narrow band O2's.
It does seem if he used his WB O2 to replace one of the narrow band O2's, you would see a lot of activity.

I have no knowledge of the replacement O2 thing other other than this.

I asked Don 95Vert his thoughts on this a while back. He advised a new bung for the WB and keeping the stock system undisturbed.

ADDITIONAL NOTE:

I just had a thought that might explain the wide range of af ratio values I see at idle. My lsa is very narrow. One would think this would contribute to a dirty idle af ratio.

Perhaps that is it

At least ... it makes sense

Grady

 

[SWYZ721]

ADDITIONAL NOTE:

I just had a thought that might explain the wide range of af ratio values I see at idle. My lsa is very narrow. One would think this would contribute to a dirty idle af ratio.

Perhaps that is it

At least ... it makes sense

Grady

That would make complete sense, as they are so sensitive they can pick that up, what's your idle set at?

Every 100RPM equates to 50 exhaust valve lifts, correct?

Therefore 500 RPM would equate to 250 exhaust valve lifts per minute, therefore ~4.1666667 valve lifts per second.

And how many readings does the WB02 make per second (which is what I believe most car electronics are rated at)