SSC 5100, 5200 related to P3191

First ever problem with my Prius after 7 years. I was driving at about 30 mph when the car lost motive power and the dash lit up with the red triangle and multiple other icons (picture upon request )
The car did not shut down.

I pulled over and shut the car down, then powered up IG-ON after a couple of minutes and saw the same dash display. My SG reported DTC P3191 which I cleared. When I restarted the car no alarms lit up on the dash display, but the ICE would not rev when I pressed the accelerator in either park or neutral. At that point I had the car towed to the dealership. I gather P3191 lights up when a problem with fuel delivery occurs.

The mechanic strikes me as quite competent (thank you!) and thinks the malfunction is related to software in the ECU and hybrid CU (?). I gather Toyota has SSCs 5100 and 5200 on the subject (reported as P50 on the invoice), and authorizes reprogramming if a problem occurs. When I pick up the car I'll request other DTCs and frame data. He also noted that the air-fuel ratio sensor wire was exposed from likely rodent gnawing on the insulation. He did not think the sensor was causing a problem related to P3191, and only recommended replacement in the near future. Any dissenting opinions that the wire may have triggered the software bug ?

If I can forward to the mechanic any questions PC might have, let me know in the next couple of hours.

PC has one other thread re: P3191
code P3191 - PriusChat Forums related to the G1 Prius.

p.s., it can be disconcerting to have a bunch of lights and the big red triangle, and not have a clue what the problem is. Between my scangauge and iPad with internet access, I was able to gather enough information to act reasonably (I hope) and not feel out of sorts. That was actually pretty cool.

 

Hi Seilerts,

I responded to your PM, thanks.
The mechanic suggested that a malfunctioning PCV, dirty MAF, spark plugs or stuck throttle plate as causes, but I have replaced or cleaned all of these in the past 6 months. I am pretty sure I overtightened the PCV valve when I installed it; do you think it might malfunction as a result ? The mechanic did say that oil had pooled in the throttle body, and since I do the oil exchanges I know that over-filling is not the root cause.

I added a few more details to my OP.

 

Thanks Seilerts,

Now that sounds like a smart, inexpensive repair rather than replacement. Do you know if I can reach the wire from below the car to apply the tape ? I presume the mechanic saw the problem from underneath the car, but I am not sure.

The mechanic did not think that a too tight PCV valve would cause the oil spooling unless I cracked the manifold cover, in which case an obvious leak would be evident. He also doubted a too tight PCV valve insertion would trip the P3191 code.

By the way, the service campaign is P50 on the invoice, not 5100 I thought he told me on the tele. OP corrected.