Juan

iTrader: (28)

I installed a Defi temp gauge and put the sensor on the TB coolant line. Im seeing 190-200F with the A/C on driving around town and on the freeway. With the A/C off, Im seeing 210-220 and the occassional 230 degrees F while driving. I have a '94 and it has the fan mod. I can hear the fans running with the A/C off and I can see the temperature drop a bit but it still seems like it should be running cooler. The temps even climb while its idling in the driveway with the hood up. The highest I saw in the driveway was 235F. I still have the plastic undertray cover on. Im planning on modding the undertray so the sides of the radiator are covered, forcing all the air through it.

The car looks like the radiator was replaced with a metal stock replacement not too long ago. This car has been my daily driver since I got it in December '03 and I havent had any problems with it. I dont see any smoke or smell coolant while driving.

Reliability mods I've done to the car since buying it:
- Vacuum hose job
- HKS DP wrapped with header wrap
- Water temp gauge
- Boost gauge

Will the Miata thermoswitch help me out? New coolant perhaps?

SpeedKing

iTrader: (4)

Which fan mod does the car have? The one with a manual switch, or the one with the pigtail connector to the ECU?

The Miata Thermoswitch shouldn't make a difference with the fan mod working properly.

Juan

iTrader: (28)

I have the one that keeps the fans on for 10 mins after the car shuts off. Is this even considered a fan mod? Which mod is more effective?

Enconsiderate

1. why did you put the sensor on the tb coolant line???

2. temps are about... ehhh... norm. I run about 170-180 F with fan mod and koyo rad. its summer time and if your running stock rad. i guess thats about the norm. perhaps you could be running a little cooler. just make sure your temp stays stable.

3. yea thats one of the fan mods. i am running the same fan mod.

Nathan Kwok

The stock ecu doesn't turn on the fans until 221F and when idling the temperature will continue to rise briefly before the fans start to have their effect. This is what you are seeing. With the A/C on, the fans always run, so you'll see steadier temps. The fan mod will only activate the fans when the switch is tripped, so if you have the switch off it shouldn't do anything. If the fans aren't coming on with the mod switch tripped then you may have somehow done it wrong.

Juan

iTrader: (28)

I didnt perform the mod myself. From what I've read, the dealer did these mods. I'm thinking about doing the mod where the fans are on whenever the car is on. I installed the sensor in the TB line because it was very easy to do and I dont have much time to drill and tap the thermostat housing. The temperature readings Im getting seem accurate since the fans come on as soon as the gauge reads 220 F. I thought it was amazing how the stock gauge sits in the middle when my Defi gauge reads anywhere from 140F all the way to 230F. When is the miata thermoswitch useful? Ideally, I would like to have the fans turn on sooner than 220F instead of having them run all the time.

skunks

that fan mod is usless! coolant is not circulating thru the engine so who the fk cares if the fans are on after you shut your car off??? it does help cool off the exterior of the engine maybe but how the hell does it help your car while its running when you are actaully gonna do damage??? do the proper/real fan mod to keep your fans on at least low while your car in on and warmed up! this can be done by grounding the relays near your airfilter.

BTW: if your car gets up to over 210 degrees, id shut it off becuase you got problems! unless your doing highspeed runs or racing in 100+degree heat, you should not be over 210 degrees!

rx7f4n4tic

How feasable would it be to just leave the switch on while your car is on? If your using e-fans then why not just leave them on all the time while your car is on. Wouldnt it help stabilize temps alot easier, for people like us who isnt putting a/c back in the car/doesnt have it anyways. At least leave it on a low setting or something. Or does the fan switch mod only have an on/off setting?

pomanferrari

iTrader: (1)

The temperature measured at the TB is 10 degrees cooler than the temperature at the filler neck where the coolant comes out of the engine. I used to have two gauges: one at the TB and the other at where the PFC reads the coolant temp. The sensor at the coolant neck is about 10 degrees higher than the TB one. Apparently, the TB is the temp of coolant as it gets to the rear rotor, the one at the filler neck is after it circulates past both front and rear rotors.

BTW, your temps at the TB are very similar to what I saw over 4 years: 190-200F during cruise, 230 in traffic with AC on. 210 w/o AC on.

legal-z

for the time being, why not just turn your driving lights on whenever you drive so the fans will come on earlier?

Mahjik

iTrader: (1)

That's a load of crap. Ignore this stuff.

You don't want to run your fans all the time. It's not needed and will cause your fan motors to wear out MUCH quicker.

If you find your car in a position that you have to have the fans on all the time to keeps the temps down, then either:

a. you are trying to keep your temps too low and are uselessly going to burn out your fans
b. have another problem causing your high temps

kwiktsi

Hows that so if the stock fans don't even come on until after 220? Something doesn't make sense here.
Joe

gmanggg

Does this work? How much earlier do they turn on?

Fumanchu

I am pretty sure it is not an exact temp. It just happens due to the extra electrical load on the system.

Fumanchu

Totally wrong. I see those temps everyday in my daily driven FD. There is nothing wrong with 210 degrees while you are in traffic or on a hot day. I don't worry until they reach about 230. At that point, my a/c is on full, bringing the temps down.

trancemaster

I think i have this problem. Unless i have the fans on my temps go up to around between 95-105C, with fans on its about 82. Could it be a bad coolant/water mix? I also noticed that ever since i installed the fan mod, if i turn em on, they wont shut off even if i turn off the switch until after i turn off the car (like 10 min after), and i'm pretty sure i did it right. What can it be?

SpeedKing

iTrader: (4)

That's correct. That's one variation of the fan mods out there.

Juan

iTrader: (28)

I installed a miata thermoswitch earlier today. I havent driven the car that much to be able to test my temperatures. I'll do that tomorrow. My "radiator cap" (on top of the thermostat housing) was bad. I took it off to add coolant and the rubber seal under the cap was very flimsy and didnt stay in place. I suspect air was getting into the system through there. I bought a new cap while I was at the dealer getting the miata thermoswitch.

Mahjik

iTrader: (1)

The stock thermostat won't start opening until around 85 C or so. 95-105 C is just fine and is not a problem. If you see 115 C, then you have problems.

Juan

iTrader: (28)

After installing the miata thermoswitch, new radiator cap and topping off the coolant, Im now seeing 195-200 F around town with or without the a/c on. The temperature seems pretty stable too. I ordered one of those radiator funnel tools to bleed the air out of the radiator but I'm still waiting on it. I'm sure I'll get some air out with it. After that, I'm planning on doing the ghetto engine bay exhaust mod and some radiator ducting.

FCdemon

a question for you: did you weld or otherwise put a shroud around the sides of the koyo? because my car is still running hot even after I put a koyo in, and from what I can tell it's either the thermostat or the lack of shrouding around the radiator. I have stock fans as well.

TurboIIGuy

when you have the a/c on the car will run cooler since you have the extra fan on and spinning to keep the a/c condensor cool. it is also blowing through the radiator as it does that.