Power Vision Information Thread
Tourer
Joined: Apr 2011
Posts: 472
Likes: 2
From: Hutchinson, Ks.
Im looking over the first log I did. I notice that out of nowhere, under no hard acceleration or deceleration, my afr drops from the usual 14.5-14.6 down to 12-1. The only other value I see that changes is kpa drops considerably at the exact same times the afr ratio drops. Why would this be?
I am running stock o2 sensors and did the log off of Jamie at fuel moto's map; one that runs great.
What does kpa even mean? Some sort of manifold pressure?
I am running stock o2 sensors and did the log off of Jamie at fuel moto's map; one that runs great.
What does kpa even mean? Some sort of manifold pressure?
Tourer
Joined: Apr 2011
Posts: 472
Likes: 2
From: Hutchinson, Ks.
Ok. So what, while at a steady rpm, would cause intake pressure to drop drastically. From say, 60 kpa, down to 20. There does not appear to be any problem with my intake or air cleaner.
Im assuming the fact that it drops down to 12-1 afr it puts itself into open loop for what is probably a second or 2, and then back into closed loop. With no real trace of why.
Stellar HDF Member
Joined: Mar 2009
Posts: 2,454
Likes: 58
From: Graysville, AL
Click the link in my sig to get a basic PV tuning guide that I put together. It is a simple set of instructions to get you going. Come back here to ask questions and we will be glad to help. You probably noticed that a lot of the 176 pages are helping one forum member or another.
I also asked a question a few pages back when the spark plug, knock sensor questions were being addressed. Fuelmoto recommends the stock plugs but would upgrading to the SE plugs cause any problems with the sensors? Thanks
Road Captain
Joined: Aug 2007
Posts: 701
Likes: 72
From: SA TX
Steady state cruise and a sudden drop in KPA would tell me that the map sensor either is going out or there may be a ground problem somewhere. AFR going to 12.1 and then back will not drop you to open loop...ECU will remain in closed loop until the AFR table entry drops below 14.6.
If you were to remain in 12.6 due to map problem...bike will go into limp home mode....don't ask me how I know all this....had a problem with an 2011. Different cause which neither DJ nor HD could figure out.
But, the ultimate answer to the problem that I had was to put the ECU into open loop so it would ignore O2 sensor input. But, diagostic codes were pinpointing MAP sensor problems.
Had to experiment to find the bottom line problem by experimentation....after MAP was replaced by dealer.
If the log shows a sudden drop in the KPA to zero and then a jump back to a normal reading, I would suspect wiring corrosion or ground problem first.
If you were to remain in 12.6 due to map problem...bike will go into limp home mode....don't ask me how I know all this....had a problem with an 2011. Different cause which neither DJ nor HD could figure out.
But, the ultimate answer to the problem that I had was to put the ECU into open loop so it would ignore O2 sensor input. But, diagostic codes were pinpointing MAP sensor problems.
Had to experiment to find the bottom line problem by experimentation....after MAP was replaced by dealer.
If the log shows a sudden drop in the KPA to zero and then a jump back to a normal reading, I would suspect wiring corrosion or ground problem first.
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Cruiser
Joined: Aug 2007
Posts: 165
Likes: 0
From: Daytona Beach
Stupid question???
OK, so I've been running logs, and I have a question. The MAP I'm using has everything from 80 KPa and down, and 4000 RPM and down changed to 0.981 Lambda.
Should I be changing any other cells?
I'm using the NB o2 sensors.
: EP
Should I be changing any other cells?
I'm using the NB o2 sensors.
: EP