k so i drive the car with ac on blast and its around like 95 degree weather. and after 20 minutes of driving the car starts to over heat slowly... but if i turn the ac off and turn the heat onto full the car go's back to normal temp. anyone have a problem like this before? theres no smoke coming from the exhaust and the car drives fine..... i took the thermostat out and put it in boiling water and it looked like it opened but about half way.

 

Shouldve replaced it...and then properly bleed the system.

 

^^ for sure, thermostat's are cheap enough. I say replace the thermostat and the radiator cap and see if that solves the issue.

 

How are your cooling fans? Both spinning?

 

+1 I had this problem with my 97, almost exactly, and it turned out to be one fan motor had seized up and wouldnt turn with ease. Replaced fan and problem solved. I believe a bad cts will cause the fans to not trigger properly also?

 

I'd check fans first, then thermostat, and if neither of those solve your problem, it may be time to replace or rod out the radiator... if you don't regularly flush your cooling system.
Had a similar problem on a mitsubishi that was never flushed over a 11 year time span - ended up replaced the radiator, and all is well again.

 

thanks for the input guys, yah the fans both turn on and i changed the cap with my friends maximas and its the same thing.... i think it might be a clogged radiator because the fluid was not lime green but a little bit dirtier. i also notice that the upper radiator hose dose not pressurize.

 

Depending on how long it's been since the last flush, if the fluid was a little bit dirtier than just lime green, there's a small chance that it is carrying corrosion from some internal parts, such as the water pump fins. When you say that the upper radiator hose does not pressurize, it brought some bad memories of my overheating problems; the water pump was not cycling the coolant at all through my cooling system. The pictures below, comparing the old and new water pumps, show the reason why. Hopefully, that will not be your case.

 

Yikes, that water pump is hard to believe! Any idea how that happened? Wrong coolant? How many miles on the Max when that happened? I know Taurus's were famous for that, have not heard of it happening with a Maxima.

Almost looks like someone put battery acid in your cooling system.

 

That wouldn't move any coolant in that condition. Was that your first guess on fixing it?

 

I really have no idea how that happened, other than due to neglect. I purchased the car with 132k miles and I realized the fluid was rusty red when it started giving me overheating problems anytime I was standing in traffic. As long as I was moving it was somewhat fine.

 

That's right; it wasn't moving any coolant at all. My first guess was a rusty radiator, so I changed it, along with the thermostat. Flushed the coolant and burped the system a few times, but the car was still overheating. I had also changed the radiator cap, just in case that was culprit. Finally I bit the bullet and decided to tackle the water pump. I replaced it and flushed the system one more time. Other than the passenger side cooling fan motor failing a few months later, and replacing the whole cooling fan assembly, I haven't had any more overheating problems. I replaced the Coolant Temperature Sensor after that, since it wasn't crazy expensive, so basically I have a fairly new coolant system.

 

man that water pumps ugly lol... but yah im going to change the radiator next week, theres no rust in its just like a grayish color. ill let u all know what happens from there.

 

 

Is there a special way on doing the coolant flush because of the water outlet pipe thermostat (water control valve)?

 

i always thought taking off the bottom hose and running the car and running 'hose' water through the system until it came out clear, was the way to do a coolant flush..

 

That is how I have always done it...

 

I prefer distilled water. fill up and drain till its dilute

 

same process though, right?

 

it takes a much longer time. you have to drain, fill up with water, let car run for 10 minutes to mix it all then let it cool down for ~2 hours, come back and drain then do the same again. I used 8 gallons of water and did it casually over two days.

 

lol ill stick w/ the hose procedure

 

your causing 'hard water deposits' from the water to clog your radiator and internal parts. "Hard water deposits" are derived from water that contains a high mineral content. This type of water usually consists of magnesium and calcium along with other compounds. After the vehicle has been heated up, and then turned off- that water will leave water spots known as calcium deposits or lime scale.

that lime scale will eventutally etch itself into any metal surfaces, causing rust. that rust will weaken metals, and eventually further clog your radiator; which will decrease the fluid flow, and increase how hard the water pump has to work.
so with increased rust building up, temps going from hot to cold on the water pump, that will weaken the impeller on the water pump- thus resulting in the image above.
(NOT ONLY WILL IT CLOG YOUR SYSTEM, BUT IT WILL ALSO BUILD UP ON THE THERMOSTAT.

-dont be cheap, or lazy. USE DISTILLED.
have you ever tried to change the thermostat on our engines? i did... trust me- its 50x's more of a pain in the anus- then just using distilled water LOL

 

pretty much sums it up...... do it once do it!

 

I'LL STILL W/ THE HOSE PROCEDURE!!! Thats why i dont fill up my cooling system with water, i use coolant. it has 'oiling properties' that prevent rust that water can cause

 

I didn't fill up with water genius. On the last drain you pour in 1 gallon 100% antifreeze and you get a 50/50 mixture. I also Used prestone superflush to flush out the system. You can do what you like with your car and stick to your beliefs but you're not following the right procedure.

 

I didnt say you or the other member filled up w/ water, you assumed I said that and you assumed wrong.

 

How do you collect it all?
A huge drain pan?

 

^ yeah right, he prolly drains it all onto the ground and lets it flood the street.

 

damn right i take my car to the back ditch and let her floowww....whats wrong with that? after the first drain its just dirty water coming out anyways...

 

hater! next time i do it i'm using my oil pan and taking it to advance, the guy said i could put it in there..whatever happens after that, is on them



LOL i use to do it this way/similiar

 

and then you wonder why the city shows up the next day to pick up the dead raccoons while your neighbor rushes her cat to the vet.

 

i dont like cats so that works out perfectly

 

"im in your engine bay, sipping on your c00lantS"

 

taste like apple kewl adez

 

You guys may want to consider one of these...not only would you not have to buy distilled water for a radiator flush, you don't ever have to worry about water spots after washing your car I've had one like this every place I've lived.

http://www.autogeek.net/clinhofi.html

 

is that like the mr clean thing

 

I think similar, but it depends on the cartridge you install in the canister. If you really want a nice no spot residue you need to get both cartridge types (spun for sediment and then soft water). Then you'll need to get two canisters (in-line with one another).

You will also have to buy replacement filter cartridges and recharge the soft water cartridge. Seems like the maintenance costs would add up quickly...

 

The way I do a flush is taking off the the TOP hose and plugging the radiator inlet port, after collecting any initial drain onto a bucket or pan from the bottom of radiator. Then running the car, with heater running on max, while feeding a garden hose with running water through the radiator, until water comes out clear from the top hose.

 

From my repair manual, these are the directions to flush the cooling system.

I did read somewhere (couldn't find it just now) that distilled water should be used when creating the coolant/water mixture.

 

alright still having the problem. i replaced the thermostat and did a flush...drove it on the highway for like 15 miles and it started to overheat again. any thoughts??? needing to take a 4hr drive next friday. HELP!!!