2008 Prius losing power - Need troubleshooting help.

gotcha. makes sense that the downstream side would look clean.

 

A slightly dirty filter should not cause driving issues

 

apparently. i think he's still diagnosing.

 

My 04 was starting to loose power around 300,000 miles gas milage dropped from 47mpg average to 42 and I noticed couldn't climb 4144 ft with cruise control set at 75mph a weekly climb I've done since I bought it. A few months later I replaced the traction Battery though did not see an improvement in my climbing power. I'm burning oil now so I figured it was old engine. Then while climbing to 8,900 feet on vacation the heat of my catalytic converter trying to burn that oil melted the welds of the exaust manifold. Now my Prius sounds like a Harley and the power is back. If you are burning oil, is exaust system back pressure causing a performance problem?


iPhone ?

 

Did you clean inside the tube? That's were the MAF sensor resides. Very delicate thin wires. The sensor you cleaned outside is MAP.

 

The same check engine light [MIL multifunction indicator bulb] as oil change time. Though your dealer would have seen the different code for catalytic converter temp sensor out of range.
I actually don't think you have a problem. I think you are beginning to learn more about the way your Prius works. Some times it puts the power of the engine to work charging the traction battery (engine revs but doesn't push the car much) this would be the case when you had been parked with your foot on the break several minutes, battery below two bars. Then when you start out the engine would rev to 2500rpm as you depresses the accelerator combining the power of the motor and Battery but using most of the motors power to charge the battery.
I had to change my thinking about the motors. One electrical motor is very powerful at slow speeds (it actually has to be limited by the automatic traction control) the other electric motor is powerful at higher speeds. Lastly the gasoline Engine runs most efficiently at 1500 and 2500. The Prius knows this, and uses the electric engines to fill in where the gasoline engine is not efficient. For example at low rpm the Prius uses the electric engines to turn the wheels and start the gasoline engine while it revs to 1500 efficiently and takes up more load then when you take your foot off the accelerator it takes the energy of an efficient spinning engine to charge the Traction Batteries. The accelerator pedal is connected to a computer that runs all three motors as a team.


iPhone ?

 

That sounds a lot like you are saying that you NEVER check the oil level yourself.
Please tell us that is not true.

This is an important thing to do........and as your car gets older, it is MORE important.

 

That is an assumption that probably is NOT true.....and is not a good excuse even if it IS true.

As a responsible car owner, you NEED to do some basic things for yourself, like check the oil and other fluids that are easily observable just by opening the hood.......looking at the tires to be sure one isn't half flat.......checking the brake lights, turn signals and headlights occasionally.
Maybe even taking a peek underneath every so often to be sure some part is not loose and ready to fall off.

 

Or else, don't be surprised if you get stuck with a major four-digit repair bill, like the engine blowing up due to lack of lubricating oil, or experiencing a no-start incident due to a failure to notice or care that the 12V battery is near death.

 

Looks like you're taking an interest simply by being here and watching the YouTube videos you mentioned. That's a great initial step. Next, read your Owners' Manual cover to cover. When you're ready, you can pop the hood and try your first oil change. This is a learning process and you'll gain confidence as you do it. You can get as dirty as you wish, but even if you don't want to get up to your elbows in grease, certain things have to get done to your car when they're due. Like the old Fram ad said, you can pay me now or pay me later.

Good luck

 

The throttle position sensor is located on the throttle body. Toyota Techstream should report a throttle opening of 60% or more when the throttle valve is fully opened by hand. If your local Meineke mechanic read the correct parameter then I would agree the TPS needs to be replaced.

However this is not a recommended procedure by Toyota, which recommends the entire throttle body assembly needs to be replaced. Hence I suggest you obtain a used throttle body assembly and a new throttle body gasket, and install those parts to address the problem.

Look at the Engine Control System section of the factory repair manual for info about the throttle body assembly.

 

You noted that the throttle body was cleaned.

Patrick, could a dirty MAF sensor cause these symptoms? Just trying to think of cheap possible solutions before breaking out the more expensive solutions.