A month or two ago, my fuel milage dropped pretty significantly. The truck's runnig really rich. I've already ruled out the O2, and CSI, and now I'm starting to lean towards a bad temperature sensor.

I grabbed my multimeter, and read infinite resistance on the sensor, on a somewhat warm engine (maybe 20-30c water temps), and I'm pretty sure this it not right. Does anyone have any information on testing the RTE temp sensor? Is it the same as the RE sensor?

While we're on the subject, the RTE has two sensors in the water neck. One is for the ECU, but I'm unsure what the other one is for. I was told it was for an ignition advance maybe? does anyone have specs on this sensor?

 

i don't even know where the temp sensor is

but i bought one

 

I thought the second plug read the temp for the cold start injector? If so, and it reads that the engine is cold constantly. It could be dumping fuel into your intake and causing your drop in mileage/rich mixture. I'm sorry I can't give you a definitive answer, I'm away from my FSM...

 

Like I said in my first post, I've already checked the cold start injector (CSI), and it's operating perfectly normal. And it uses a thermoswitch, not a sensor.

 

I wasn't wearing my thinking cap. Thats good to know about the cold start injector however. I was wondering what controlled it.

 

The CSI is controlled by a temperature controlled switch, near the lower front of the intake manifold IIRC. I know the vague location, but can't describe it specifically. It's stuck in a coolant passage somewhere. There should also be another thermoswitch for the A/C, and a third temp sensor for the gauge.

Anyways, I just got off the phone with my buddy Jeff, a Toyota EPC mad man, and he confirmed that the RTE sensor is identical to the RE sensor, as well as a ton of other vehicles. The second sensor is ALSO for the ECU, but it's purpose so far has yet to be determined. Anyways, the 2nd sensor is also found on AW11 MR2s, and 3Y/4Y minivans.

I also bit the bullet, and ordered a compete FSM set for the RTE, as I've seen next to no info on these motors. Price wasn't bad, but it's going to take like 5 months for them to show up. I guess there aren't a lot of 22R-TE FSMs lying around.