p0a0f & p3000 code at same time- solved? maybe...

Long time lurker, first time poster. I had some major issues, then googled the bejeesus out of this site, and it looks like i solved my issue

We live in New Orleans and it gets swampy, to say the least. For the last 6 weeks (end of july through labor day), we had the red triangle of death come on during the middle of the day, when it's most hot and humid. This caused the triangle as well as all sort of other lights go off. The first time it happened, the car limped til it couldnt go any further. The second time, same thing. From then on, wife noticed that the motor was really rough when the gas pedal was feathered and going 15-25 mph. It was like the ICE was coming on and off in a rough way. Then one day, wife is driving the car home from work, and car limped, she pulled over, and killed the power. She waited a few minutes and thought she would restart the car. no dice. Car would turn on (windows up and down, display on, etc) but would not engage Drive or Reverse. First time that ever happened.

Vehicle towed to mechanic. I called the shop ive been going to for years and I asked, "do you have toyota techstream?". "yea we can get in the prius, bring it by", the owner said. Well, they had autel maxisys which spits out codes for toyota but not subcodes. I got the P0A0F and P3000. long story short, $4,ooo quote at the dealership.

With help from prius chat and some googling, i realized that the p3000 code is set off whenever the ICE gas engine aka air/fuel/spark part of the car malfunctions. Full disclosure- I called Electron Automotive, which I learned about on Hoovies Garage on youtube, and Tyler the owner told me that. SO what is wrong? PA0A0F has 5 subcodes, 2 of which have to do with running out of gas.

I ordered a $50 mini vci, googled up the 4000 page pdf of the repair manual, and right now im struggling to get techstream registration to work.

As I alluded to, i did a lot of searching on diagnostic trouble codes DTCs on this site, and the mass air flow sensor one stuck out. I had really rough ride from 15-25 mph, the toyota prius quiteness sweet spot. Well, i finally took off the air box and got at the MAF sensor, as well as the throttle body. Throttle body was pretty caked on with black crud. Pulled back on spring and the tension on that spring was like what one of those old school hand exercisers felt like when youre a little kid. When i looked at MAF, it was supposed to be a glass globule matchstick looking thing... it was totally caked in black crud. As if the 180 degrees of front air flow facing surface area had burnt oily material collecting. the small back area facing the throttle body had a little bit of clear area. when i pulled the MAF from the air box, i sprayed CRC maf cleaner on it and sprayed it clean til it looked like a glass matchstick

While the fuel pump relay is still suspect, and I didnt have daylight for the spark plugs, I put everything back together. we started the car, and it worked fine. no lights or error codes. she ran the car around the block, totally smooth at 15-25 mph. I think the rough ride was the MR1 and MR2 engines going on and off in such a haphazard way that I had an ECU going crazy.

Last weird thing which may be a concurrent issue: on the way to a grocery store, wife pumps gas while on one tick on the fuel gauge aka almost empty and can only put in 4.5 gallons. is the fuel gauge messed up? We were empty and then were full with half a tank. I been reading about the bladder errors. I think the MAf errors set off the fuel gauge into it's own errors

when i can get tech stream working, i will mess with the codes, clear them, see if they come back etc

so this might be a novel, but i just wanted to submit an anecdotal story and contribute to the site. maybe someday, somebody will read this while thinking "I don't have $4,000!!!". Ill update when tech stream is up and running and confirm whether MAF was just the first domino knocking over the rest.. the Toyota Domino.. great name for a car.

PK