So I thought I had this taken care of but I guess not. Did a coolant flush and used Prestone super flush to clean everything out. Also changed thermostat bc the last one was stuck closed. Maybe I'm putting the thermostat in wrong? Is it supposed to go with the springs inside the motor, or the springs facing the radiator?
Overheating round 4!
- Thread starter Jordysoso
- Start date
Head gasket was done a year ago due to dumbasses before me leaving a dowel pin out of the motor. Water pump was swapped with a gates one and timing belt was done at that time as well as thermostat and an oem rad cap from online Mazda parts. Valvoline did a coolant flush and put DEXCOOL in it. So I flushed that out per instructions with the prestone super flush. I did a burp and filled the system properly about a half hour ago but not sure if all air is out. I haven't driven it yet and now I have the proper green colored coolant in not the DEXCOOL
If the overflow was boiling but the temp gauge was at normal then I would suspect the rad cap.
If the temp gauge rose above half then I would suspect the thermostat.
You could remove the thermostat entirely and reassemble everything without it to rule out the thermostat as the cause (thermostats can be as fussy and annoying to diagnose as our coils)
You may still have some bubbles in the system but if it isn't too many then they should self purge with the heating and cooling cycles of the engine. (turning on the heat helps to flush bubbles out of the heater core.)
I don't know what the dexcool does with our engines.
If I were you I would just drive it and see what happens and see if things settle down for you. Remember to crank the heat on full snort if the temp gauge rises above half.
If the temp gauge rose above half then I would suspect the thermostat.
You could remove the thermostat entirely and reassemble everything without it to rule out the thermostat as the cause (thermostats can be as fussy and annoying to diagnose as our coils)
You may still have some bubbles in the system but if it isn't too many then they should self purge with the heating and cooling cycles of the engine. (turning on the heat helps to flush bubbles out of the heater core.)
I don't know what the dexcool does with our engines.
If I were you I would just drive it and see what happens and see if things settle down for you. Remember to crank the heat on full snort if the temp gauge rises above half.
I was running water and super flush, with the new thermostat. Driving on turnpike the temp gauge started to rise above half. I drained the super flush and water out, flushed again, hecked thermostat to insure it wasn't stuck and it wasn't, but the last one was stuck and the DEXCOOL was in it. They have different silicates in the different coolants and DEXCOOL is mainly gm vehicles. I'm thinking the recent over heating was just from the water boiling and evaporating. I put the new coolant in after I flushed out the super flush and drove around city driving stop and go. No problems since and both fans work on the radiator. I drove for a total of an hour stop and go and stopping at two locations with the car off for roughly 10-15 mins per location. Like I said no problems at all for now but I don't wanna risk another $250 tow. Maybe coolant temp sensor possibly?
You can be 96% safe in an overheat condition by cranking on your heat at fan position four and driving it home.
Turn off the AC and all extra loads and keep an eye on the temp gauge.
As long as you don't pass out behind the wheel due to heat exhaustion. Just roll down the windows and blow the heat at your passenger (it's OK if they pass out.)
That DEXCOOL may have been the issue,... different boiling points or something ???
The thermostat can still misbehave and present itself as normal by the time you check it.
I'm quite confident that you can get home to diagnose further if it acts up again,... without the tow truck and that expense.
(PS. Get yourself an Android phone and the Torque app and it will tell you EXACTLY what your temp is and not what the ECU wants to tell your temp gauge... It does way more than that too,.. way cool.
If you've already got the phone it's a $35 investment or less.)
Turn off the AC and all extra loads and keep an eye on the temp gauge.
As long as you don't pass out behind the wheel due to heat exhaustion. Just roll down the windows and blow the heat at your passenger (it's OK if they pass out.)
That DEXCOOL may have been the issue,... different boiling points or something ???
The thermostat can still misbehave and present itself as normal by the time you check it.
I'm quite confident that you can get home to diagnose further if it acts up again,... without the tow truck and that expense.
(PS. Get yourself an Android phone and the Torque app and it will tell you EXACTLY what your temp is and not what the ECU wants to tell your temp gauge... It does way more than that too,.. way cool.
If you've already got the phone it's a $35 investment or less.)
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I believe same boiling points but the different silicates can cause problems from what I read. Also the hour that I drove it today it was 90, sunny, quite humid and my ac was full blast, temp gauge didn't rise above half at all. Still had bubbles in coolant tank but my guess is remainder of air in the system.
Thought i might just throw this in here.
The P5 runs very high Water and Oil temps... even on a good system... just the way it is unfortunateley (hence all the oil pressure issues people have)
Turning on the AC on the P5 will actually REDUCE water temps. As the AC fan is much larger than the radiator thermo.
If you are overheating... my advice would be turn heater to max hot and press the AC button.4doesnt put much load on the system, but does kick in the extra fan.
by the sounds of it... when you did all of your flush and refill... you have actuallly got an air lock in your coolant system.
to avoid this, next time jack the front of the car up whilst filling the radiator. This makes the cap the highest point in the system. Also use the top of a softdrink bottle as a funnell to have some pressure on the water entering the system. you should also remove the cap from the over flow to allow easy escape for air.
The P5 runs very high Water and Oil temps... even on a good system... just the way it is unfortunateley (hence all the oil pressure issues people have)
Turning on the AC on the P5 will actually REDUCE water temps. As the AC fan is much larger than the radiator thermo.
If you are overheating... my advice would be turn heater to max hot and press the AC button.4doesnt put much load on the system, but does kick in the extra fan.
by the sounds of it... when you did all of your flush and refill... you have actuallly got an air lock in your coolant system.
to avoid this, next time jack the front of the car up whilst filling the radiator. This makes the cap the highest point in the system. Also use the top of a softdrink bottle as a funnell to have some pressure on the water entering the system. you should also remove the cap from the over flow to allow easy escape for air.
Thanks,... That's good to know,... I never woulda thunk it.
I was curious as to how that happens ??? Hotter oil is thinner, reducing oil pressure ???
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i didnt know it until i started monitoring my vital signs lol.
P5 likes to operate at 110C oil temp normally, 115C @ highway and 118C when giving it a bit... and this is normal for a P5
i have never had pressure issues myself, but i put that down to correct oil weight, fully synthetic, keeping it alway sright on the Full line and low km service intervals... couple that with a not so good oil pump... and you get issues.
any oil running at these temps... especialy non synthetic will loose their viscosity quickly... resulting in oil pressure drop.
So I was driving down the highway again, 68 mph not even 8 miles and my temp gauge starts goin up. Crank the heater and everything is ok, started to rise at a stand still. I've already put over 2k in repairs to the car and don't wanna put a s*** ton more in. Anybody have any ideas? I thought I bled all the air bubbles out. And I've been driving it on the new coolant now for a good amount of miles. I'm super confused at where to go from here it's like deja vu. I use full synthetic 5w-30 either valvoline or castrol. But what does oil have to do with the coolant system if the job of the cooling system is to cool and oil system is lubrication other than reducing friction?
Just a couple of ideas,...
Was your overflow boiling ???
Try touching the upper rad hose to see if it is hot (while in rising temp gauge mode). If there is no fluid running through the rad, the hose won't be super hot.
It may still be a faulty thermostat (even though it's new) they can be as fussy as our ignition coils.
Removing the thermostat completely will help to verify that.
I remember reading about a guy (with a P5) with overheating problems and it turned out that his temp gauge was faulty. He verified that by using an OBDII bluetooth with the Torque app and his cell phone.
His temp gauge rose but his OBDII showed his temperature was normal. He replaced his instrument cluster and that fixed it.
Good luck.
(sorry about the oil talk,... that was me drifting off topic again)
Was your overflow boiling ???
Try touching the upper rad hose to see if it is hot (while in rising temp gauge mode). If there is no fluid running through the rad, the hose won't be super hot.
It may still be a faulty thermostat (even though it's new) they can be as fussy as our ignition coils.
Removing the thermostat completely will help to verify that.
I remember reading about a guy (with a P5) with overheating problems and it turned out that his temp gauge was faulty. He verified that by using an OBDII bluetooth with the Torque app and his cell phone.
His temp gauge rose but his OBDII showed his temperature was normal. He replaced his instrument cluster and that fixed it.
Good luck.
(sorry about the oil talk,... that was me drifting off topic again)
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drifting off topic is cool, i know ive done it a good amount of times the past couple years i been here. ill probably end up pulling the thermostat. for the above instructions i need an OBD2 code reader right? sadly i have an iphone so the torque app is a no go. i thought about buying a cheap ass 7" android tablet with a dash mount that would strictly stay in the car for monitoring purposes but i need the funds for it first. i wonder if anyone wants to trade one for a 4th gen ipod touch??....lol
