So a couple days ago I realized that my water running temp was 4 degrees C higher than normal.. It usually runs at 79 C when its cold out and 83 in the summer. But for some reason it showed 83 C....running temp. It didn't read any higher the whole time it ran..but it's different and it makes me nervous. Also...Every morning I warm my car up before driving it.. when it hits 60 degrees C it kicks up a few hundred RPM. This morning it was different.... checked oil... A okay. Checked water level.. about a cup low..topped it off. Started the car..nothing different. But the car didn't kick up a few hundred RPM at 60 C. It kicked up around 72-73 degrees C. The car even idled at 79 like normal up until I drove to a nearby coffee shop. Driving the Water Temp rose only to 80 C... Maybe a bad thermostat?....How long do they last? Or Electrical?

93 touring Built motor

3mm seals
Gt40R
FMI
Apexi PFC
Fans turn on
Water level is normal
Oil Level is normal
Temperature is cold

Like I said the only thing i can think of is that maybe the rain did something last week...but It's running fine...

 

also I have a AEM Water Meth injection kit... It's low..but it only sprays at WOT and I havn't gotten into boost because of it..

 

this could be almost anything, if you're not noticing anything else wrong I wouldn't worry about it, 83C is perfectly safe, I usually see 85 while driving around. If you really wanna drop the temps a bit more, set your fans to turn on at a lower speed via the PFC.

 

Yea your right.. but if it's been running a certain way since it's been tunned.. for the past 6 months at a certain degree... and all the sudden does something different i'd be ignorant not to suspect something is up.. With my experience with rotaries... not taking knote of this is asking for disaster.. Maybe i'll flush my coolant system this week..

 

Um, there is absolutely nothing wrong with your car. If you were running at 103 degrees all of a sudden, then I'd understand the need to start a thread

 

there's always a chance your water temp sensor is going bad and doesn't read right anymore. I've seen a couple read off. The factory thermostat doesn't open until 82C.

 

Your thermostat could also be a bit lazy.

Do you have a temp gauge on your car as well as the PowerFC? Do their temps agree?

Dale

 

no...thats a good idea though. Maybe i'll pick up a new Thermostat..

 

remember when I said that something was a little different from normal and everyone told me not to worry about it? Well today after a Correct coolant flush I was on my way to the gas station and I noticed that my temperature was rising... thought it might be my water temp sensor acting up so I looked at my car water guage.. All the sudden I see 102 C and th needle on my cluster guage is approaching the middle hot side of the latter.. I shut it down and pull into a gas station near my house. The Oil light is on .... so i check my oil level... Oil is A okay... my water temp light is on.... so I check the water/coolant level... A tad low but nothing odder than normal.. Called AAA and towed the car home..

So my question now is what do i do? can I take my computer to a tuner? or do i have to have my car towed? I dont have a datalogit either and i'm almost certain no one in this valley does either....

 

were the fans coming on?

 

Did you check the thermostat?? It could have been sticking. Probably the cheapest/easiest thing to check.
Man i would kill for 83C temps in the summer, or winter for that matter. I run cooler than most Fds in my area at 88-89C summer or winter.

 

Yes sir... fans came on...

 

No I didn't... I'll try it tomorrow.. but why would that throw my Oil light and Water temp Light? THanks guys...

 

Man,you guys freak out when you see 85c? I'd be happy just to see my fd stay at 90c I live in the desert and 95c is like cake with whipecream to me lol

 

Looks like you have a bonified temperature issue if the gauge in the dash has increased (it runs off a separate sensor) as well as the PFC indicating higher temperatures that nominally indicated.

1. Replace thermostat
2. Replace pressure cap
3. You said the coolant was changed; Quite possible the inherent bubble in the engine was not purged out. This is the biggest cause of high temperatures. I remove the coolant hose from the top of the throttle body during fill to vent out air and wedge in a funnel in the fill port so the liquid level during fill can be above the cap top.
4. If after all that still high temps look at your water pump...

As far as the light - are you sure it was oil pressure or the low coolant level light?? Did the dash buzzer sound?

The only other rational explaination is the coolant is being blown out of the system - and this indication is well understood......

 

Let us/me know what the problem is/was.
I have noticed my own car running a few degrees hotter than normal the last few weeks. With the water temps moving up and down more than they used to.
I am going to look at a few things tomorrow.

 

I'll check the coolant level like tt mott said and change my sensors as well... Get back to you guys in a couple hours with updates on the coolant level etc..

 

[QUOTE=ttmott;9833363]

As far as the light - are you sure it was oil pressure or the low coolant level light?? Did the dash buzzer sound?QUOTE]

Well I think there was an air bubble in the system like you said...so I used the funnel and un did the water line tot he throttle body to help vent it...and filled it up. But when I put my key in... the oil light and water temp light were still on....started the car and they stayed on... let it idle for about 2 min and shut it off...

Havn't replaced the thermostat yet but why is my oil light on? And No I heard no buzzing from the dash....

 

[QUOTE=mannykiller;9834042]Sounds like your alternator may be TU or the alternator voltage regulator output or output wire (white/black) is shorted to ground. If this happens the OverHeat Exh System, Charge, Coolant Level, and Oil Level lights will come on; at least according to the schematics. If no buzzer then the dash CPU is not detecting low coolant level which further lends creedance to the alternator as the problem. Check the alternator output with a meter.

To be clear the lights are:
Oil Level (not pressure)
Coolant Level (not temperature)

 

[QUOTE=ttmott;9834077]
I'll check the alternator output this evening as a friend has a meter.. also..I just let the car idle all the way up till warm up... it held normal at 79 C and after holding it at 3K for about 3 seconds it went up to 85... then cooled back down to 80 C...


Maybe its the alternator like you said... So i'll have to take my car into mazda to get these lights turned off then prob right? Thanks

 

[QUOTE=mannykiller;9834096]You should be able to pull the electrical connector from the alternator when idling. If the lights go out you have isolated the problem to the alternator.

 

oh yea..

The very top guage on my stock 93 cluster.. Very top being Oil Pressure but if i'm low on oil my light comes on. The very lowest guage being water/coolant temp. Both of those are on..

 

FYI the temperatures you are reaching are not a problem at all. It's perfectly normal for a water temperature to fluctuate within the operating range of the thermostat. Piston engines do it too. The factory thermostat doesn't even open completely until 95 C--rotaries have had that same thermostat range for the past 40 years. From the factory the fans don't come on until 105C. I'm not saying that fan trigger temperature is a good thing, but I can tell you right now that somebody was driving around at that temperature for years.

If you have a leak, find it (pressure testers help). If you want to check your thermostat, pull it out and put it in a pot of water and see if it opens properly. But don't freak out about the car hitting 85 or 90 C.

 

I understand the fluctuations.. it just seems weird to me that there's a change all of the sudden and for no apparent reason. thanks though!

 

Let the car idle again..... Lights turned off.. Must've been the air bubble in the system... though temps are still deviating much more than usual...