fuel/afr load varies with engine off with throttle change

[skikir]

I was looking at the AFR or VE table (I forget which but probably both) with ECU connected and engine off. The load was about 85 with throttle closed which I thought was low but when I opened the throttle the reading went to almost 100. Now, correct me if I'm wrong, if the Load is an indicator of manifold pressure and with the engine off and no flow past the throttle I would imagine the MAP would be indicating ambient air pressure and changing the throttle position should not change the reading. I've always suspected something was not right and not getting an accurate reading at different throttle settings would seem to answer some nagging feelings I've had. Why would MAP change with Throttle position. Is there a Calibration setting I'm missing?

[2swe]

depends on algorithm you use for tuning, I bet it's ITB mode..

[skikir]

yes it is. Please expound on that observation!

[Paul_VR6]

Itb uses a blend of tps and map for load.

[skikir]

Well that adds multi-dimensional considerations but then again a hundred percent load at zero RPMs is hard to understand in my mind in the first place.

[2swe]

can you uploadan MSQ?

ITB mode uses bottom part of your VE table for Speed-density, and top part of VE table for Alpha-N.
to switch from SD to AN, two conditions must be met - MAP must be 90% (and more) of initial MAP reading during power up, and second condition - TPS treshold (set in "ITB mode TPS switchpoints" curve) must be met.

In your case, with engine not running, the first condition is already met, because your MAP is actually 100% of initial MAP reading.
when you open your throttles past treshold, load starts to grow, with WOT load is 100%.
this is how ITB mode works...