rlx101

Coolant Temperature Sensor (CTS) goes bad (does not report correct temp) on some LS400's and causes reduced gas mileage. I found discussion about this here: https://www.clublexus.com/forums/sho...d.php?t=376713

The part is only $29.99 at autozne and will return the money after few fill ups if it works.
My question is, would it make sense to replace this part on a high mileage lexus es300? looks like many LS400 owners had positive results (see link above) after replacing CTS even though it does not through any codes.
We got '95 es300 with over 150kmiles and been averaging under 20mpg mixed driving.

fiddy yen

I would imagine so, but it would depend on a number of factors:

1. whether ours are similar or the same as the LS series
2. if the ES models get corroded or overheat.

I would recommend changing it (I mean its only $30 isn't it?) and see for yourself. I'd be interested to see if this will help, however i do not have the time right now for it.

Plus i don't know if I trust myself yet to go play around in the engine.

GEORGE_JET

Alldata states that the 92 es300 sensor should read 0.2 to 0.4 k at 176deg, or 2 to 3k at 70 deg. If it is reading correct, there would be no point in replacing. If it is reading high, than all means replace it. If the computer thinks that the engine is cold, it will prevent the engine from entering closed loop operation. The computer also adds extra gas when the engine is cold (like a old fashion choke). Both issues would reduce gas mileage. With a OBDII car, you could hook it up to universal scanners and read the actual temp without any hassels.