I have an SC300 with a 2jzgte swap and I'm having temp issues as well. I have an aftermarket digital temp guage and would like to go back to the stock temp guage as my first step in seeing if its the guage.
So to make a long story short does anybody have a wiring diagram to help me hook up the stock guage?

Thanks and sorry for the noob question. I have been a member for about 6 months but re-register'd because I could not remember my board name since its been about 3-4 months since I have been on CL.

Thanks everyone in advance,
Gregg

 

Well i have the same prob, xcept that i had my lights changed by Lextech Lighting, and OLT told me that they might have just not aligned the needles back properly and that all i would have to do is pull em off and put it where its supposed to be at normal running temps....

 

LOL shhhh dont give away the 1JZ temp needle secret

 

i change my engine control sensor an wire temp sensor (auto zone parts) and my gauge started to be that way. im a put the stock sensor back in ( an see if its that). i completly broke the wire temp sensor (bitter) so i have to use this one till i see how much is a stock wire temp sensor.

 

ok i found a local junk sc300 an got the wire temp sensor off of it an now my temp gauge is back to normal. the sensor with the green plug is ok to use auto zone sensor. the white one is not

 

Uhmmm . . . so WTH is a 'WIRE' temp sensor anyway

 

Im guessing he meant water temp sensor. Who would want to know the temp of a wire?

 

Sometimes your wires will overheat if your electro-thermostat fails.

 

alright so my needle has been rising slightly an it has been an eye opener for me.

Ive had my car for 9 months and its been well maintained by the previous owner (dealer records) but the fan was able to be stopped by hand when i first bought the car. Never had any overheating issues. A month ago, my belt tensioner needed replacing. So i replaced the water pump, timing belt, seals and thermostat. The thermostat was an OEM and I picked up some Antifreeze from the dealer as well. Car running perfect for the next week.

I planned a 1000 mile trip (500 each way) an about 400 miles gone in the trip is when I first noticed the gauge increase. I pulled over immediately and popped the hood. Antifreeze leaking out onto the water pump!!! So I let the car cool off for about 30 minutes before i drove off, i had to keep the heater blasting so I wouldnt heat up again. Made it to a local gas station/ mechanic shop.

First thing i had him do was make sure my thermostat was in correctly an than do the boiling water trick. The thermostat wasnt the problem. He told me it was my fan clutch since he was able to stop it, but I never had a problem with that in the past and wouldnt expect it to happen on a long road trip but more so in city driving. He bypassed the clutch so it would run @ higher speeds. My car now sounds like an airplane for those of you who are wondering. Although this trick did manage to cool my engine down for another 2 weeks, the needle rose again today. Therefore i am not convinced it was the fan clutch to begin with.

After reading this whole thread, I saw a bunch of incidents that were familiar to mine but still no ideas as to what it can be.

Does anyone have any idea what else it might be??

 

bump ..... anyone can help ?

 

Couple thoughts:
Is your radiator shroud in place?
Is your radiator cap holding pressure properly?
Are your AC condenser and radiator cooling fins clear of debris clogging the airflow through them?

Also, a few more questions might help narrow the causes too.
Does it overheat when cruising at highway speeds? Or does it only overheat when going slower or stop and go? Any drips of coolant leaking after parking overnight?

BTW, fan blades can normally be stopped hand when their clutch isn't engaged; they're just sympathetically freewheeling then.

 

Goodtogo

you said something about overheating at highway speeds

My sc300 is overheating at highway speeds. I tend to drive between 75 -85
with the AC on and she's been overheating only with the ac on? But not on the back roads

when it overheats I cut the AC off and cut the heat on she cools right down and stays cool??
replaced the fan clutch last week and it was fine for a week.

no water in the oil. No water coming out of the radiator cap.No leaks or drips

93 with 101,000 miles on her

any help would be great

 

sorry good2go

 

Yeah, the bit about overheating at speed was mostly just eliminating the fan from the issue; at speed, the passive airflow being forced through the radiator is usually enough to cool the engine. In your case, where AC seems to affect it, I'd probably also check to see if the AC condenser fins are seriously clogged up (blocking proper airflow), as well as just a bunch of typical stuff: coolant level, air in system, water pump and thermostat working ok, serpentine belt not slipping under increased load from AC compressor (if that's the case, might also check that you vibration damper pulley is becoming separated). This also assumes that your engine is generally running properly and not overheating under load because timing is off or something.

 

Just curious how you test for stopping the fan by hand? Just jam your hand in amongst the blades and hope the clutch is worn out? LOL