From o2 sensor to engine replacement in 10 days?

Turkey baster will not work, don't waste your time or the baster. The oil is in the oil pan, which is under the cylinders. The drain bolt is really easy to reach without raising the car. You need to go on your belly and contort a bit, but it's not impossible. I would still put those jack stand on the top of my shopping list. Best $20 you'll spend on car repair. With those you can even use that joke of a jack that's included with the car. If you do want to buy a good hydraulic jack, then you can do so at Harbor Freight, even. Do not go for those "fancy" aluminum racing models. They usually take more effort to operate and are not worth the extra expense. Get a basic steel one like this. These two tools will expand your ability to deal with car things greatly. You'll be able to change your oil in 15 minutes and know exactly what was done instead of trusting strangers with your car. Beat of luck, I hope you resolve this puzzle.

 

I just had a thought about removing a small amount of oil without lifting the car. You can do so via the dipstick tube using a syringe attached to a long skinny tube (clear fish aquarium tube, for example). If you don't have syringe, then maybe some sort of suction device, possibly even the same turkey baster, but I think the baster is not that good at maintaining vacuum once it has picked up fluid (just remember how it does on the bird. It drips the moment you fill it, but the bird is right there, so it's ok).

 

There's a difference between invalid data and incorrect data. The ECU can detect invalid data- open circuit, short circuit, or unchanging values, but there's only one actual sensor so it's not like it can do a crosscheck to make sure it's getting good quality data.

I have another Japanese car, and I've owned it long enough to learn that if I put an OEM sensor in the upstream position it will run great. If I put another one in from one of several big, well known quality brands... it runs terribly. It's not supposed to be that way, but that's how it is.

I think Other Mechanic Friend is giving good advice.

 

If the engine works well when it is cold and the engine ECU is operating open-loop mode without accounting for the A/F ratio sensor input, then I agree it is reasonable to try replacing that sensor with the correct Toyota part.

 

Did anybody ask the question if whether the sensors are made by Denso?

 

Post #2 : From o2 sensor to engine replacement in 10 days? | PriusChat

 

Answered post #4

Air/Fuel Sensor Part# REPT960917
4-wire, OE Replacement, Direct Fit, M18-1.5 Thread Size, Threaded in Mounting Style, 7/8in. Hex Size, Male Connector

Non OEM Part. THIS IS PROBABLY THE PROBLEM!!!

 

Near as I can tell, Denso was the OE supplier of these for Toyota. They list their 234-9056 part as the retail replacement. I can now see why a weird socket was involved.

 

Odd looking bird. What does the wrench look like?
https://www.rockauto.com/en/catalog/toyota,2006,prius,1.5l+l4+electric/gas,1432870,exhaust+&+emission,oxygen+(o2)+sensor,5132

 

Amazon write up is better.

Check out the reviews. According to the write up it’s not an O2 sensor, it’s a Air Fuel Ratio sensor? That could cause no power.

 

You will need a compression tester and probably a sub screen in Techstream

 

Compression testing a prius sounds interesting. I gather that you would need to use Techstream to crank-but-not-start the engine somehow?

Backing up a moment, I have relied on compression testing as a bedrock-primitive test for every piston engine I ever needed to work on, and it's great data to have. On the other hand it doesn't sound that easy to actually do on a prius, and I'm not experienced enough with these cars to say if it's an appropriate commitment of resources at this time.

I've done it a couple times on my winter beater. Since the spark plugs have to come out for it I usually combine it with a plug change. But only maybe every 3rd change

 

Not just a Prius anymore, a lot of cars have push button starting. The days of key turning are long gone.

 

I think your non OEM sensor is causing your issues. It probably isn't seated properly either, that's why there is loud noise is in the front.

Whenever you change a Toyota sensor, you have to use the exact same one (Denso)

 

I gotta admit, this lines up really tight. We know the sensor was changed, we know it was changed for a generic part, we know a bad seal would absolutely account for serious noise potential up front, plus an exhaust leak-slash-air-leak at that location would make even a genuine sensor send false data, and we know that false or even late lambda data leads to low power, poor running, high fuel consumption and more...

Now just gotta hope that the threads in the exhaust manifold aren't too munged up from this misfit sensor. Good to get eyes on it.

 

This is correct. Techstream has a diagnostic screen that allows you to crank the engine. All spark plugs would be removed, and the tester screwed into one spark plug hole. Crank the engine a few revolutions until the gauge stops moving upwards. Record the pressure reading, then move to the next spark plug hole and repeat.

If you find the reading is abnormally low, squirt a tablespoon of engine oil into the spark plug hole, and repeat. If the reading goes up that shows the rings are shot. If the reading does not go up that means the valves are shot. This helps you to decide whether it is economical to repair the engine or not. It is easier to remove the head and take to a machine shop, than to rework the cylinder block.

For the fuel pressure test it is necessary to fabricate a test line with a special fitting to connect a fuel pressure gauge into the fuel line. This should be done by an experienced mechanic, probably too much for a newbie DIYer without running the risk of causing a fire, etc.

 

I think if someone would have caught the non original AF sensor being installed in Post #4, we would save ourselves 300 posts. This would be an easy fixer to determine if it's the cause.....but I'm pretty confident it is with the code and loud noise

 

Don't you mean 299?

Oh...

 

300
And the car is still broken.