Fan's NOT TURNING on
 

i was idling in my driveway this morning...(hotter day) looked up and noticed the temps rising up towards 200F, kept going up to 220..right past 220 the fans kick on well today it went up to 230-231!!! and they still didnt kick on i turned the heater on full blast and flipped my fan mod switch

Should i be worried about hitting 230F at idle for a brief period of time? And why are my fans not switching automatically could it be caused by the Peter Farrel ecu?

Thats pretty warm. Most common cause of the fans not working is a problem with the relays. I have extras is you need them.

The car will get hot if its just idling. The car is cooled by air flowing over/through the radiator and oil cooler. If you are idling, there is no airflow so it will run hotter.

As mentioned, the relays are part of the fan operation. I would also inspect the fans themselves to make sure you can put power directly to them and they work. Also, the Thermoswitch on the back of the waterpump housing would be something else to check *IF* everything else checks out ok.

let me make this a little more clear

- car runs perfect when cruising rarely over 190F
- fans switch on perfectly with my switch...i usually hit the switch all the time above 185 degrees (scared of running any hotter)

once in a while i would test it (this was with the stock ecu setup) incase someone were to drive my car without knowing about the fan switch mod....well the fans would always flip themselves on right above 220F on my DEFI gauge

today i tested it out (this is with the PFS installed (purple box)) i just sat in the driveway for a few mins and it kept rising...at 220 i was expecting the fans to kick on..i got out and looked nothing...kept rising at 230 they still didn't come on...my stock gauge read below center still so i allowed it to go a little above 230____they still did not come on so i flipped the switch and the header at 230ish degrees and the temps dropped immediately


my first concern : has any engine damage occured, and can it possibly occur at 230 degrees!?!!?!?!!?!??? am i going to start the car tomorrow to find that the seals are bad?

second concern: is the new ecu causing the relays not to work...the fan IS getting power becuz i always use my switch

and last, where and how do u install the fc thermoswitch..is it a new thermostat?

Failed thermo sensor . We get that on mx5's, its a common problem.

No, a thermoswitch is a thermoswitch (ie, switches when a preset temp is reached). Why did you put the purple motor eater in instead of a PFC?

And no, engine damage has not occurred unless your cooling system has no pressure.

Sorry there was suppost to be a question mark in my post

ie Thermo sensor ?

becuz it was $300 and I'm not looking to do a bunch of mods...just a little extra fuel support for 12lbs

so what about the thermoswitch what should i do? and is 230 considered over heated?

230F is not overheating. Its hot, but not overheating.

As far as the thermoswitch, pull it and test it.

230 at idle most likely won't cause any damage. I think you're OK.

You really need to get water temps under control - a cool engine is a long-lasting and healthy engine. Bare minimum, FC thermoswitch. Here's my post on the topic -

https://www.rx7club.com/3rd-gen-archives-73/fc-thermoswitch-fd-447606/

If you want to really keep things under control, get the HKS Fan Controller. I absolutely love mine - ROCK solid water temps, 80-90 deg. C driving around town in HOT Florida weather with the AC on, nothing special to do, just get in the car and drive. Here's my writeup all about it -

http://www.clubrx.org/default.asp?id...ntent=41&mnu=3

I would also just make 100% sure your cooling system is healthy. No coolant leaks, good thermostat, etc.

Dale

230F is not overheating. The fans should kick on at about 220F if the lights are on. 230F is about right for the fans activating without the lights.

Get the FC thermoswitch. If I still had the car I would have done it. It's a cheap, insurance mod.

thanks ryan...the car def runs great though!!!!!!!!.....i'm coming through ohio soon on my way to indiana university...u want me to stop by?

depends on if you want your car stolen !! ;)

by the way, it still wouldn't hurt ... while you're in there ... to make sure all of you ran relays/motors/etc seem to be operating properly.

once you get the FC thermoswitch it'll just be a matter of re-learning the behavior of the cooling system.......... emissions or not, i still think it was ridiculous of Mazda to make the FD's run that hot.