Overheating issues

[Rngray5]

I ran a search, and consulted my Haynes, but other input is always helpful. My Thermostat went a week or so ago, so i replaced it. my car still wants to overheat occationally, usually in stop and go traffic, and random other times. The condensor fan (thats what people i know have refered to it as, the little fan on the drivers side) kicks on, but the passenger side one does not. so i made a trip to the JY and yanked one, only to have it not run either. this makes me think it's the sensor on the thermostat housing, but i have read there is another sensor at the bottom of the radiator on FI models. I have 2 extra engines to pull things off of, so tomorrow i will try replacing the sensor on the housing, but i'm just curious to what other people think it might be ( when it starts to overheat, i can see the thermostat kick in and it usually drops back down)

[A20A1]

All 3g's have a sensor on the bottom of the radiator to controll the fan.

I'm not sure what the sensors on the thermostat housing do...
I would think that the radiator is the primary sensor you need to replace...

there is a themperature guage sensor on the thermostat housing for EFI... but that only sends the signal to your guage cluster.

[anchovies]

The thermostat housing switch also controls the fan at a higher temp compared to the one at the bottom of the radiator.
Actually i think it's lower temp (can't remember right now).
But it might as well be your temp sender that is faulty. I had the same problem for a while and was scratching my head changing this and that and could not believe a new aftermarket sender could give hotter than normal readings. But it did.

[88LXi/87CRXSi]

Sounds like the sensor in the t/s housing is working ok, have you checked fuse #9 in the under hood fuse box? Might also be a bad rad fan relay located in the same fusebox. If you have a meter or test light, with the temp sensor connecter to the rad sensor jumpered and key in run position, there should be 12 V at the fan motor connecter.

[Rngray5]

well i replaced the sensor at the bottom of the radiator, and that didn't solve it. (stupid OEM sensor cost me $51) but in the process i realized that i replaced the wrong thing on my thermostat housing (i switched the little black one, and i think it's one of the 2 others, so i'll switch them tomorrow) i did check all the fuses and they all seem ok, the more i think about it, the more it's probably the one on the thermostat housing seeing as when my thermostat went it prevented the sensors from being cooled, and i prolly fried one of them as i limped it it work ( it broke after an Italian final very far from home)

[wthramann]

What happens when you turn A/C on?

[Rngray5]

i don't know ididn't turn my A/C on yet. I usually don't use my A/C When i have my heat on it doesn't overheat. I checked the fan, it works when it's hooked up to power, all the sensors have been switched and the fuses checked. the Relay under the hood checks out also. I'm stumped. it only does it after i drive for 30 min or so and get caught in stop and go driving. even then it heats up to 75% or so then drops back down once i start moving. if i Idle when it's hot, it will heat up to around 90% and if i have the hood up the fan doesn't kick on. i am going to replace the thermostat again just for the heck of it.

[88LXi/87CRXSi]

Remember to bleed the air out!

[Rngray5]

I think i had some air in the system, it seems to have gotten better. when i turn on the a/c the fan kicks on now.

[POS carb]

ok it should go like this:
A/c should kick on at least the condensor fan
the other fan should come on to keep the temp needle centered. If it raises while stuck in traffic it's a fan problem. If it's when you are driving it's a thermostat/pump/clog issue