Knock sensor problems? (Scan tool graphs)

[cross6]

Borrowed my brother in law's scan tool to check out my maf/ect/02 sensors (trying to fix a rough idle/bad mpg problem).

Noticed the knock sensor showing a lot of activity that trends with engine load/rpm.

I let the tank run to fumes and put premium in the tank and drove it around all day. Didn't change the knock sensor activity.

I can't hear the engine knocking. I know chain rattle can confuse the knock sensor, but I don't hear chain rattle, even with a mechanic's stethoscope.

Any ideas what I'm looking at here? Not sure what the knock sensor should look like on a scan tool.

(2004 Mountaineer 4.0 Flex fuel 163K miles)

Ignition timing advance fluctuates from 10-15 degrees during rough idle situation.

 

[esclamada]

I don't know if the knock sensor will help with that kind of problem.
Try graphing your pre-cat Oxygen Sensor (O1S1 or 02S1) and see the switch between lean and rich. Along with it, look at your SFTRIM and LFTRIM, the LFTRIM should be somewhere between 0-10%, 0-3% is really good. Lower and beyond this values means that there's a vacuum leak (air in the system, LEAN) or too much fuel (leaky injectors, RICH)


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MY MOUNTY
http://www.facebook.com/diyfordexplorer/photos_albums

 

[cross6]

I don't know if the knock sensor will help with that kind of problem.
Try graphing your pre-cat Oxygen Sensor (O1S1 or 02S1) and see the switch between lean and rich. Along with it, look at your SFTRIM and LFTRIM, the LFTRIM should be somewhere between 0-10%, 0-3% is really good. Lower and beyond this values means that there's a vacuum leak (air in the system, LEAN) or too much fuel (leaky injectors, RICH)


-----------------------------------------------------------
MY MOUNTY
http://www.facebook.com/diyfordexplorer/photos_albums

Yep everything else checked out. Trims are at 1% and 2%. Upstream O2s switching correctly. MAF is good, ECT & IAT are accurate. Only 3 misfires during an entire day of driving.

 

[cross6]

Does anyone know what the knock sensor values should be? Don't know if what I'm looking at is good or bad...