I also went open loop to see what would happen and I got the same 13 to 16 bounce. I started messing with the MAF scaling table but didn't seem to do much but I never added fuel or subtracted fuel in the fuel map. I got annoyed and just flashed my original rom back.

 

What Rom were you using? Tephra V7 94170715?

 

No, I use 88590715 but your problem sounds exactly like mine.

 

What values do you have for your maf scaling map?

 

Here is what I have for MAF scaling, I bumped up 0-50 to compensate for my intake and fuel trims but ever since I replaced my front o2 sensor the fuel trims have changed. Ill rescale my injectors, latency, and MAF tomorrow.

 

I bumped mine up even more. Like around 19=393.7, 25=402.5, 50=421.3. Try that and see what happens.

 

I'll try that tomorrow morning when the car is cold.

 

You could try it now too. Just force the car into open loop by changing (FAA) bit 4 to 0. That will enable full time open loop. Do that and start the car. Observe AFR. Gradually increase your MAF scaling until it idles around 14.7afr or slightly richer. Then re-adjust the rest of your MAF scaling map along with the comp map to smooth it out. Once your idle is good, you should be able to switch bit 4 back to 1. Then from there, just fine tune the maps based off of fuel trims.

 

So after a couple months of messing with this, I finally resolved the issue. The problem I have been having was due to the car almost immediately entering closed loop op after cold starts. By raising the temp required before initiating closed loop op, the issue has been 100% fully resolved. The reason it took me so long to figure this out is because the 9417 Tephra Roms do not have this table defined, I had to manually add it to the xml.

4 days later and issue is still 100% gone!