About 2 months ago when I came here to Phoenix my car was running hot every now and again when I would start driving after sitting at a stop light. I think that running a little warm like that put extra strain on my radiator and caused it to leak due to the extra built up pressure.

I replaced my radiator with a KOYO radiator and also the radiator cap.

After I replaced my radiator I have had no problems until today. The temperatures here in PHX were much lower than normal for june, we were mostly in the 90's. The last few days have heated up to 110* or so though and I have noticed the temp gauge climb 2 times today.

It only happens with the AC on, after I have already been driving for a good 25-30 min, and after I have been stopped at a traffic signal for a minute or two. The needle only moves about 2 notches. I turn off the AC and it went back down to normal. Turn the AC on and it didn't duplicate the problem again for another 10 min. Like I said, it only happened twice.


So, I have new radiator, obviously have changed out the coolant (even added some Redline Water Wetter). I changed out the T-stat a couple months ago. Coolant level was to the MAX line yesterday when I checked fluids.



What do you think is the issue???

 

Perhaps some air pockets trapped inside of the engine from the flush. Did you unscrew the air release valve a few times? This happened to me a few weeks ago and to others as well, it seems to be a common issue for our engines. If you turn on the heat and fans to max then you might hear some gurgling noise, because of this issue.

 

I've done a burp job on the system a few times. I plan on doing it again though.

I still don't know if this is the issue though...

 

I've driven the car perfectly fine for the last 4 weeks, the heat was in the 90's just not 110 like yesterday.

 

Ya sounds like an air pocket in the system.

 

Couple heating questions... distilled water vs tap water...why?

Also, a lower temp thermostat - can that cause any issues? If so, how?

 

The same exact problem I am having with my car. Check your fans. I am going to be replacing mines out.

 

mine are new.

 

Strange... Even so, have you checked under you hood when you car temp guage is rising to see if your fans are running full speed while you're a/c is running?

I'm not sure what else could be the problem is since you pretty much did everything, radiator, thermostat, etc.

You are having the exact same symptoms as me, and for me, my fans are not operating consistantly. So I am pretty sure for my fix, it's the fans.

 

One other thing you can check is to see if your radiator cap is keeping pressure. Also had this issue and couldn't fully remove all the air pockets from my system.

 

I replaced the radiator cap when I replaced the radiator.

Like I said, its not a constant problem. Its happened before...but its only happened twice and both times were yesterday.

 

Same here, I got a new radiator cap and it was defective when it came. It was only able to hold half the pressure depending how I tighten the cap. If it was on all the way it would hold around half the pressure. Half way on, for some reason it was able to hold more pressure. Something was wrong with the gasket and the spring. I had to put back on the stock one until i received a replacement.

 

tollboothwilley, keep us posted, i would like to know also as we are both having the same problems with our cars.

 

NYC kid.. I bet you have an air bubble. have you burped the system?

When I replaced the t-stat I used a 350z version which opens at a lower temp(170* vs 180*). Some people claim that this could be the problem. I'm not sold on the idea, but I'm not throwing it out.

I need to *burp* the system again and see if the problem persists.

 

nope, i dont know how to burp the system, or bleed the air. ive never done it before. but how do you get air into the cooling system anyways? i never ever opened my radiator cap before.

I will be replacing my fans soon, and hopefully that will fix the problem. I don't drive my car often. So i'm not sure what else it may be.