1992 Es 300

[juno_reaction]

I was wondering what KNOCK SENSORS are and how much would they cost for a '92 ES 300 and whether or not they're an important par of the car. Are they?

[Toysrme]

They're small peizo microphones that the ECU uses to determine when the onset of detonation/pre-ignition in the engine is. If it's detected, the ECU retards the ignition timing until it goes away, then adances it back.

Are they important to the mechanical operation? No

Are they important? Yes. With a knock sensor code, the engine goes into limp mode. Ignition timing is set to base timing (5-10*btdc depening on the code), will not advance (Horrible for power output/economy), and the ECU will dump lots of fuel into the engine. Depending on what else is going on, the ECU can lock-out the overdrive in the transmission.

Basically... The engine output sucks hind tit, along with it's economy.

They're about $20-50 used, $75-150 new & located under the lower intake manifold on the engine block (In the V).

You can see them in this picture.