SR doesn't reach operating temp

[hayai_240]

Currently, my SR motor never reaches operating temp. I've replaced my thermostat w/ a new OEM one and also installed a real water temp gauge w/ the sensor located in the upper radiator hose. I've re-bled my cooling system multiple times and there are no leaks. I am currently running a aluminum koyo radiator and stock clutch fan w/ shroud. I live in the NW so current temp. is around the mid 30s to low 40s.

While driving around last night for about 40 minutes, my water temp gauge read about 140*F and never went above that. My car idles extremely high around 1500-1700rpms because I believe the ecu keeps the car in warm up mode.

Do you guys have any ideas as to what could be causing this? Would replacing both my coolant sensors do anything? What other items should I replace or test?

[Landers]

For the record my sr doesnt go above 160 unless i flog the thing heavy (Drifting)....even during the summer months. But yea 140 is low.

[johngriff]

Idle should be stable under 140.

Running cold is fine, sounds like your problem lies elsewhere. High idle?

TPS
Timing
Coolant Temp Sensor
Ecu Screw
IACV Screw (do this one last).

[IStop4NoMan]

Mine runs at that temp with the exact same setup. i think that koyo is overkill for the engine with a stock fan. mine stays at about 140, occationally goes to 150.

[RedtopTech]

That would be no good on a setup with forged pistons. There wouldnt be enough expansion in order to take up the larger clearance in the bores. Just something to think about.

[rps13sr20det]

I have the same problem in Canada. I haven't even had my temp gauge read until im pushing my car in the summer time. And usually if i push the car. I get a small read and usually it will just drop right away. Im thinking wiring problem or sensor.. I could use the advice as well

[Gjohnson7]

Man, I never thought of that. My head is off the car and I'm about to tear into it, but I installed a Tarus fan a couple of weeks ago and ran the car for a while to make sure it was wired correctly. I used an aftermarket temp switch and it was suppose to cut the fan on at 165 degrees. Guess what? Fan never turned on, and I was worried I would overheat so I shut the car off. Maybe that's why it never turned on.

[hayai_240]

I definately want to get this issue fixed asap because constantly running your motor at this low temp can cause engine failure.

Someone suggested that i check the clutch fan to see how much resistance there is when attempting to spin the fan when the motor is shut off. If it is too tight, then the fan is spinning to fast and thus overcooling the engine. I'm going to check this out tomorrow.

Also, i removed my stock shroud and put a piece of cardboard in front of the radiator to block some of the cooling. Just testing to see if my current setup is overcooling and is the cause for my low water temps. Will give an update w/ my results.

[Addicted2Kouki]

maybe your thermostat is staying open?

[mnmax]

maybe your thermostat is staying open?
i'm going to have to agree there...

[((sr)) kelly]

i wish my sr stayed at 140 lol


but yeh... your thermostat is deff staying open.. unless you have a crazy dual pass radiator with a gigantic fan, like on my fathers Rb..or someother crazy setup

does your car ever pull itself out of open loop?

[OBEEWON]

Im putting money on the coolant temp sensor (ecu). That would also explain the high idle. Maybe even the part of the harness to the coolant temp sensor.

What is your A/F? If its slightly rich then the above is likely.

[hayai_240]

Thanks for all the suggestions guys but I figured out my problem. My shroud was too efficient! LOL. After removing my shroud and block part of my radiator w/ cardboard my car got up to temp in under 10 minutes and the idle has stabilized around 900rpms. This goes to show how important and how big of a diff using the stock shroud is. After about 10 minutes of stop and go traffic my temp got to about 210*F. I am going to remove the cardboard in front of my radiator to see what kind of effects it has on my water temps.

Oh yeah, for those that thought it was my thermostat, i already replaced that w/ a new OEM thermo.

[txrxs]

Overcooling ftl. I had the same problem with my car. You may want to run a switch to turn your fans off and on. This will give you a little more control then just blocking the rad off.