I have a 2000 RX 300 (155K miles) and it won't go into shift into overdrive. I took it to a mechanic and the diagnostics came back with a PO 171 Fuel System Lean and PO 325 Knock Sensor Bank 1.

They cleaned the mass air flow sensor for me. But, I am debating on replacing the harness or (2) Knock Sensors, based on feedback from the dealer and readings.

I took the car to my trusty independent garage mechanic and got CEL codes on both Knock Sensors now. He tested the sensors and they read fine. Is there a way to read the codes after putting on the harness?

Has anyone heard of issue with knock sensors going bad? Or a site the sells economical sensors. The dealer is charging $200 each.

 

Yup, knock sensors can lock you out of Overdrive. We've had "many" people run into this, just replace the sensor and you should be fine.

 

There is enough effort and if you replace the recommend parts, you should replace both senors and harnesses. No point in repeating the effort in few months.

Salim

 

I ordered (2) sensor online through eBay for $107 ttl, and then paid extra for overnight shipping. I plan on putting a new harness, (2) knock sensors, plugs, gaskets, and coolant.

Can't wait to have this done.

 

Be sure to use OEM sensors.

 

x2 OEM only.

Salim