Did replacing my timing belt cause my knock sensors to fail? What is happening?

Yes.

 

Should be a piece of cake I guess.

 

The check engine light for knock sensor doesn't mean immediately replace both sensors. It means go check the wiring and then test the knock sensors with a multimeter. Most likely they are still perfectly good and that can easily be verified by testing. Like others have said it's more likely a broken wire or maybe just a disconnected wire. $1000 no way.

 

If the connector can be replace I'd say go that route. Unfortunately our go to guy for toyota parts is kinda busy with other things outside of the forum...bummer...

 

I went through this on a Sienna and it turned out to be a faulty Timing Belt tensioner.

Make sure they changed yours and that it wasn't China crap.

Mine was in a Toyota bag but was counterfeit off EvilBay (not AirCabMan's kit)

 

Had a tensioner snap on me, in half. OEM. It might've been that I put too much pressure on it with the compression tool but the tool wasn't completely all the way down though.

 

On these parts I just go to the dealership,
Probably paid to much but I know they are OEM

 

i am doubting my local dealers 'master mechanics' abilities

some of them have probably not seen a 1st gen tacoma in over a decade

 

I’m curious to know how much they charged for the timing belt and water pump replacement out of that $2500.
Did they itemize the invoice and can you tell us?

 

Can the knock sensors be checked without taking the intake off.
Testing the knock sensors with the wires through the knock sensor harness on the top of the engine?
I would think u can

 

Usually the test is to hook an ohmmeter to the sensor, either directly or at a connector on the harness somewhere, then tap the sensor and verify that the electrical resistance changes briefly. I'm unsure how easy it is to tap in the area of the knock sensor on the V6 with the intake installed. The repair manual gives a procedure to hook an oscilloscope up to verify it's waveform with the engine running.

The sensor is just a simple piezoelectric crystal that changes electrical resistance with the pressure caused by vibrations. The computer monitors these fluctuations in resistance and interprets them as caused by pinging in the engine, and then adjusts the ignition timing to prevent the pinging.

Usually when the check engine light comes on for a knock sensor the computer is seeing a complete short circuit in the sensor or wiring, or a completely open circuit. It's not doing any sort of sophisticated test to trigger the code. And there is a different code for the left and right knock sensor. I find it unlikely that both failed simultaneously.

In short, you should be able to at least verify the resistance in the circuit through the harness. The knock sensors should have a resistance of 1 MOhm or higher but not infinite (no continuity). Ohmmeter needs to be set to measure in that range.