Problem with 2001 Prius - Red Triangle and code 3191

Here is what I have going on....

Red Triangle and code 3191. Computer shows problem with the car - not the battery. I looked at your forums and found that I may have a dirty throttle body - I checked and Yup! I removed the throttle body completely and cleaned it well. Still having the same problems although it does seem to run better when it is running.

Here are my symptoms:
Only cranks about 1 in 3 attempts. When it cranks it starts right up. When it is running it runs / sounds very good. - Also you can not turn the ignition on and let it sit at all before hitting the start position. To get it to start you have to turn the key on, and within about 1 second go to the start position. Otherwise it will not start at all.

I thought well maybe ECU??? Luckily I have an identical one of these and a 2002 as well (prius junkie.) I swapped the two ecu's ( the engine ecu and the hv ecu - they are hooked together and I just swapped the whole assembly.)

Results: No change on either vehicle. The one without a problem still has no problem, the one with the problem still has the big red triangle.

Any ideas would sure be appreciated!!