URD 7th injector kit and UltraGauge readings

As some of you may be aware, I installed a TRD supercharger on my 2000 Tacoma V6 a few years ago. I bought an UltraGauge when I installed the supercharger I also have a URD 7th injector kit, but I installed it just this year. The UltraGauge displays all sorts of interesting information, including fuel consumption. The fuel consumption displayed by the UltraGauge had been accurate for years, but with the installation of the URD 7th injector kit, my actual fuel mileage has been a bit lower the what the UG calculates. Is this due to the fact the the 7th injector is outside the control of the ECU? It is the only explanation that makes sense to me.

 

That's sounds good to me too. You could verify if you have a boost gauge. The URD controller does not activate the 7th injector till after 3 PSI of boost.
Try a mileage check on a flat freeway run without traffic...depending where you live this maybe easy said than done. Attempt to never exceed 3 PSI boost during the mileage test. I would expect your calculated MPG to be more inline with the UltraGauge. If not maybe troubleshoot for a leaky 7th injector.

 

I don't think that's true. The Split Second software allows me to customize at what boost pressure and RPM the 7th injector is activated.

 

Yea if you change the Map B settings in the R4 software. My default map B from URD has nothing but 0s till 4 PSI of boost (I was incorrect in my previous post. There is no enrichment till 4 PSI not 3 PSI). Also looking at the Injector B % in R4 shows 0 till 4 PSI will drive testing.

What are the cell values in your Map B before 4 PSI?

 

I don't recall for certain and I don't have the map handy, but I think I start adding fuel at 1.5 or 2 PSI. I have the injector running 1.1 milliseconds. At 8 PSI I think I have it running closer to 3 ms.

 

Now it maybe possible that the URD mapping is different between the 2000 and 2004 Tacoma's.
I have a 2004.

If you look at these tuning videos notice that there are all zeros before 4 PSI. Also notice in the lower center window that Injector B is 0 mS till the 4 PSI threshhold.
This tells me that there is no enrichment till 4 PSI with my URD system.
https://www.tacomaworld.com/threads/supercharger-tuning-etc.540976/page-3#post-17620731

I did try adjusting the leading edge Map B values higher but that only messed up the A/F ratio. During the transition from on boost to off boost the A/F would overshoot up and down quite a bit a few oscillation before stablizing. I'm figuring that maybe the system is still in closed loop and is fighting the extra enrichment at the lower boost levels.