Wide Bands??
 

I run 2 wide band AFR probes. One ( Innovate) is in cylinder 4 pipe about 12 inches from the exhaust valve. The other AFX is in the beginning of the collector.
I realize the AFX will not be accurate at low rpms due to location and cam overlap.
But even at higher rpms the AFX is consistently showing a richer mixture. An example is at 6000 in high gear the Innovate will show 14.5 while the AFX will show 13.2
Seems like if I tune off the AFX to a 13.2 (or so) number the car runs best.
I doubt one cylinder could be that much leaner. I have swapped the injectors, and each cylinder has it's own throttle body (all equal).
I've been led to believe that if the wide band sensors are functioning they are working.
Is this normal to have numbers this far apart?

Re: Wide Bands??
 

It in not uncommon to have cylinder to cylinder variation of more than 1.0AFR.We have individual cylinder wideband on our dyno,and even with the best possible induction distribution we see 1.0 afr or more variation,Plenum manifilds see traffic in various directions affected by firing order and valve timing events.Bill C.

Re: Wide Bands??
 

I have 3 different AFR systems. One is Innovate, one is AFX and one is out of Canada. The AFX has always read better than Innovate. I purchased a test canister to compare all. I open air calibrated all then test all 3. The Canadian read within .1 of the AFX. Innovate was off by .4. I have run all 3 on my dyno. I jetted by AFR number. The AFX and Canada unit did not vary. I finally read the plugs and I could see a difference with the innovate. Once I established a base line of plug reading and AFR reading, we always got in the ball park in a pull, then we looked at power. The Canadian unit can be read as Bluetooth. Luv the crap out of that. I recommend you open air calibrate each one side by side and see what readings you have. Then swap the O2 sensors from unit to unit and repeat air calibration and see what happens.
reed

Re: Wide Bands??
 

The plugs are different but I can try to put the AFX in the number 4 pipe and compare them at an idle.
I haven't recalibrated either one in a while. I might try that first.

Re: Wide Bands??
 

Art
I had the same problem on the Units having different pig tails so I made up plugs for each one to allow swapping. Got all thru Radio Shack. And in doing so I found a cheaper high volume O2 sensor and I use the same O2 on all units now.
reed

Re: Wide Bands??
 

I have had many vehicles through my shop with Inovate wide bands installed. I have never seen one correct. They are very popular with Internet kids. I don't know why. Maybe they are cheaper?

The one on my dyno always reads with AEM units, FAST units, the internal logger in FAST ECUs and BS3 ECUs. Showing 1. leaner with those is not uncommon. I would put that Inovate deal on Craigslist. When I dyno my engine on an engine dyno my FAST XFI wide band has always agreed with the dyno's 8 wide band system also after I get all eight cylinders in line.

Art, I don't think it's where your sensors are located. I would use the one in the collector as you have found to do. You are seeing what I have seen with the Inovate set up.

Re: Wide Bands??
 

I put The AFX in because I was told that the Innovate was slower to respond. And would be better for track tuning. I only used the innovate to be able to tune low rpms (idle).
I haven't recalibrated either one since I first put them in. I'm a little shy to calibrate them now because I have a number (13.4) that the car runs best on. That is what I shoot for in high gear going up the track.

Re: Wide Bands??
 

Also if you are running leaded gas, there could be response and accuracy issues depending on how long they have seen lead. Sometimes they can be "cleaned" if run with unleaded gas for awhile. My Olds Q4 used to need new sensors a few times per year.