DupermanDave

Where are the temperature sensors located on the 22re? I know where the one for the instrument cluster is, but where's the water temperature sensor?

Will a faulty temperature sensor cause a surging idle and burning/coolant? My idle surge is almost fixed (thanks to adjusting the TPS) but now, while it's warming up, it will start to surge when hitting a specific RPM while the engine is warming up. It only surges when the engine is warming up or has warmed up, cooled down a bit and it still slightly warm.

As for burning coolant, I'm losing coolant and looking at a cheaper fix other than a new radiator, so I'm trying to justify buying a new temp sensor

-edit-
https://www.yotatech.com/forums/f120...-issue-166254/

This post helped a lot, but still doesn't answer my questions.

abecedarian

the ecu's temp sensor should be on the front of the intake manifold, connector pointing at the radiator, closest to the engine and green in color, IIRC. the black one is the cold start time switch.

DupermanDave

I'm colorblind, so my green temp sensor and cold start injector look about the same color shade to me.

But this sensor, the one pointing to the radiator, is the one I need to worry about that might be affecting my idle?

4runnerx3

abecedarian

hmm... there are two sensors on front of the manifold, pointing at the radiator. the one closest the engine should be the coolant sensor.

edit- thanks 4runnerx3

DupermanDave

Thanks. I remember I was trying to remove those when I had the head and intake hot tanked. They're pretty stuck in there. I remember I couldnt remove them with the engine apart, I doubt I'll be able to get it off when it's in the truck.

DupermanDave

I was just thinking last night while warming up the truck. Would this affect the surging idle when the brake pedal is pushed? What relation does the brake pedal/fuel injectors/TPS have with this sensor?

22mr2

If your idles changing alot when pushing down the brake it could be a leak in the diaphragm on the vacuum booster

abecedarian

I cannot confirm but there is information stating that when the idle is above a certain speed, and I've heard 1100 and 1300 rpm's mentioned, that the ECU will cut the injectors if the throttle is closed and you are in 2wd. This means the idle can bounce up and down. Try putting the selector in 4wd and see if it continues.

DupermanDave

I'll give that a shot next time it starts to happen. Hasn't happened in a few driving sessions now. I might just forget about it and not worry since it's almost all done.

DupermanDave

It did it again this morning (but stopped after a mile) and while I was at a red light, I stuck it in 4wd and it stopped. I took it out of 4wd and it kept going. Put it back in and it stopped. What does this mean?

abecedarian

means your idle is too high. it's a 'feature' built into the ecu to help with engine braking- let off the gas pedal and if the rpm's are still up, meaning you're in gear, stepping on the brakes cuts the injectors so there's more drag on the driveline. also helps save fuel.
it doesn't do it in 4wd presumably because if you're in 4wd there's a reason and you don't want to risk losing traction.

DupermanDave

Hmm. I feel like I have the idle set perfectly, it's about 800 rpms now. if i set it lower, it feels like it will go down to 200rpms and then it sputters and almost stalls.

DupermanDave

I have another temperature sensor question. Will a bad temperature sensor make the engine idle really rough and seem like it's missing?

How do you test the coolant temp sensor?

4runnerx3

A bad water temp or air temp sensor will cause the ecm to mess up air fuel ratio and run rich.

DupermanDave

is there a procedure to test these sensors? are they in the FSM?

-edit-
found out how to test it. seems a little tedious and I'll just spend the $20 for a new one.

Can these be removed with any socket wrench or is there a special too to remove these? i remember when my engine was apart i tried my hardest to remove them both and couldnt break them loose.

DupermanDave

has anyone here ever had a coolant temp sensor go bad and cause a really rough idle? I'm wanting some feedback before I blow through $50 on a sensor

frank133

Great Thread! check out some of these sensors... http://www.motionmarketplace.com/marketing/autonics/ and http://www.motionmarketplace.com/mar...utor/index.php