Replacing Coolant Temp Sensor on 93 Camry V6 Wagon

[cycliste]

I don't really know what I'm doing, I've fixed a car once, previously.

A gentleman with a code reader says I've got a coolant sensor problem (more precisely, "#22 22 Open or short circuit with coolant temperature sensor circuit" as described here: http://www.toyoland.com/repairs.html) .

So I've just bought a new coolant temperature sensor and am trying to replace my old one.

Chiltons and Haynes both tell me I need to drain the engine of coolant.

Ugh!

Is that entirely necessary? Given what appears to be the location of the sensor, it looks like (and again, I don't speak with much experience or authority) I can replace the thing without doing that. One of the silly reasons I want to think I don't have to drain coolant is because the gentleman with the code reader knows I don't know what I'm doing, that the first thing I've ever done to a car was clean the IAC, and he still talked like it would be a simple procedure for me to get the part, go home, and replace the coolant sensor.

I'm fixing what appears to be a common stalling-while-hot issue. In addition to responding and thanking to/for replies here, I'll eventually post a narrative of my whole series of adventures with IAC, EGR, MAF, etc, when I really think I've got the problem solved.

[hill8570]

Hmmmm. Never saw a code reader that could do OBD I -- I've always just read the the blinking "check engine" light. Whatever...let's assume you actually are seeing a DTC 22 (although the facts are contradictory -- a DTC 22 will cause the engine computer to default to "warmed up", so you'd have hard starting when cold, not hot).

Anywho, to replace the ECT, just drop the coolant level in the radiator a couple of inches so you don't have it dribbling out of the ECT hole while you work (I just drain into a clean bucket, then pour it back into the radiator and radiator overflow when I'm done). Remove the old ECT, put a little blue threadsealer (Permatex Blue or similar) on the threads of the new ECT, assuming it didn't come with pre-sealed threads (blue goop already on the threads), and install the new ECT. Torque to roughly 20 ft/lbs (i.e, tighten it, but don't go pulling a Hercules on it).

[rusty9]

depends which sensor it is. there's one on the engine outlet, and one on the bottom of the radiator. stalling when hot is also a symptom of a failing distributor.

and is it really so hard to put a bucket under a drain plug?