I have a 2013 GS 350 awd. When I start it in the mornings when it is cold out my check engine light comes on. When I read the codes it tells me its the MAF and the air temp sensor. Other times when it warms up or if it is warm out side it runs good for a little while then the check engine light will come on flashing. I will start to lose power like it don't want to go. It will start shaking. And then I will have a misfire code. When I pull over shut the car off and start it again everything will be back to normal. I have replaced the MAF and air temp sensor. Cleaned the fuel system and throttle body checked for vacuum leaks. One time I noticed my exhaust on the drivers side was red hot. My cats are not clogged and no exhaust leaks. I'm kinda lost so any advice would be great. Thanks for reading.

 

This sounds like one of two things:

1 - There's a wire that's stripped and shorting against metal somewhere (MAF and AIT are voltage driven anyway)
2 - The ECU is throwing out incorrect data. It could need a new OEM flash, or maybe a connector is loose.

I don't know for sure, as I've only done surface work on Toyotas, but I've repaired hundreds of American cars and this is usually what's up. I honestly think #1 is a good fit. Hopefully someone else with more knowledge can chime in too. I can only imagine how frustrating this is.

 

I had a similar problem with another vehicle - Honda CRV. Turns out that mice had made a home in the engine bay and chewed through some wires.

 

You hitting it with techstream or a generic obd2? See if you know anyone with the techstream software(any toyota nuts should have it) in the hope it gives you more information. Ie if the circuit is going open/closed circuit or a high resistance reading.

This might sosou dumb but how old is your battery?

 

The battery is only about a year old. I dont have that program but I will look into it. About 3 days ago I looked at every wire connection I could find and push them all together to make sure everything was connected. So far I havent had any issues with it and I drive it daily. Today it is 14 degrees out and it is running amazing. I didnt notice any connections loose but maybe there was one that was just enough not to get the connection it needed. Thanks for all the help. If anything happens ill be sure to update.