Po330 And Po171

[zockslexus]

Hello all!!

I have not been here in what feels like a few years. After all, there has been nothing wrong with my ES. I have 276,xxx on her and she finally popped a few codes.

PO330 - Knock sensor 2 circuit bank 2

and

PO171 - system to lean, bank 1

Can anyone tell me where to start to get this fixed? I would rather not get taken advantage of at a dealer or some shop...

Where is the knock sensor? Anyone have experience with these codes?

Lately, she hesitates HEAVILY when I accelerate now...would love to get it cleaned up and push her past 300,xxx miles!!

Thanks for all that you do.

[lexis lexus]

Hi,

The knock sensors are located in the valley under the intake manifold. Usually the code occurs when there's no signal coming into the ECM. This either means the knock sensor is dead or the wiring has broken. Having seen how crisped the wires get in the harness connecting the two knock sensors to the connector located just behind cylinder #5 (the valley is like a small blast furnace, no ventilation at all to speak of there...), it's more likely to be wiring than the sensors (which are mucho expensive new and solid state piezo electric vibration devices, generating a signal when they vibrate).

As recently discussed (July), by George. You can jump the front sensor wire to the rear one near the connector and see if the code is relieved. That'll help decide wire/sensor question and help avoid a several hour job of replacing harness/sensors. Might want to check continuity between the connector and the ECM as well.

Not sure what the 0171 code means but leaning out the mixture, or not being able to lean it out, may cause the stumbling. Need to read more about that. Like to hear what others experience has been w/ this code.

LL

[Lexlogic]

Hi,

The knock sensors are located in the valley under the intake manifold. Usually the code occurs when there's no signal coming into the ECM. This either means the knock sensor is dead or the wiring has broken. Having seen how crisped the wires get in the harness connecting the two knock sensors to the connector located just behind cylinder #5 (the valley is like a small blast furnace, no ventilation at all to speak of there...), it's more likely to be wiring than the sensors (which are mucho expensive new and solid state piezo electric vibration devices, generating a signal when they vibrate).

As recently discussed (July), by George. You can jump the front sensor wire to the rear one near the connector and see if the code is relieved. That'll help decide wire/sensor question and help avoid a several hour job of replacing harness/sensors. Might want to check continuity between the connector and the ECM as well.

Not sure what the 0171 code means but leaning out the mixture, or not being able to lean it out, may cause the stumbling. Need to read more about that. Like to hear what others experience has been w/ this code.

LL

For code 0171 clean the MAF Sensor Click