Ant96GLE

iTrader: (4)

I'm been having some overheating issues with my car recently. I changed my water pump about 2 months ago and everything was working fine. On a 200 mile trip, all highway about 2 weeks ago, I had my cruise set to 75-80. Slowly but surely the temperature guage starts going up until it reaches about 3/4 of the way up. I slow down to about 60 and the car cools back off to normal temperature.

Ever since I havent really had much highway miles, its been all city driving. Until yesterday just driving around normaly the temperature needle starts moving up again. I changed the thermostat and it still does the same thing.

Tonight as I was driving home, I had my music blasting and the temperature guage was slowly but surely going up and the car was overheating again, all with normal city driving.. nothing over 40mph. Coincidentally, as the music was hitting some bass, the needle was bouncing up and down. I have no clue whats going on. Anyone have any insight?

mansurxk

iTrader: (14)

hows your antifreeze/water mixture? meaning what % is it at, and check your drivebelts, not sure why it would be cooler at 60 mph than 80 with all that airflow cooling the radiator, id check the mixtur eand the belts to start off, a loose belt might not be driving the pump hard enough tocool it at high speeds, im stumped too, does it cool down if you turn on the heater when this happens? you should put the heater on full blast and see if the needle goes down quicker

Ant96GLE

iTrader: (4)

I'm not really sure. Last time I flushed the system was last summer. When the water pump was changed, most of the fluid was taken out but it was replaced and mixed with some water... its not exactly 50/50 thats for sure.

Would more water or more coolant cause it to over heat?

Edit: I did put the heater on to cool off the engine and it went down within a few minutes back to normal. I havent changed the belts but now that you bring it up... I might try that since they look like they need to be changed.

mansurxk

iTrader: (14)

well you could go 60/40, but ideally i think it calls for 50/50, whens the last time you change your belts? after 60/40, you lose effectiveness, coolant needs water to operate, it raises the boiling point, and lowers the freezing point to give you protection year round, again...check for play in your belts, check if thers significant restrictions in the radiator or grille, another thing to check for is the radiator cap to see if it maintains pressure, the cap plays a HUGE part in the cooling process

Ant96GLE

iTrader: (4)

I'm going to change the cap tomorrow just for the hell of it. I do think I have more water than coolant in there... but I'll see what I can do with that. I might do a little flushing action. Like i said before, the belts arent in the best condition and havent been changed as far as I've had the car. Thanks for your help. I'll see what I can do.

mansurxk

iTrader: (14)

go for 50/50 mixture, and bleed the system so theres no airpockets, i dont remember how to purge it of air, im sure othermembers would know

Nismo

iTrader: (18)

thermostat isnt installed backwards correct?

serenity97

Well I had a similar problem. The needle would keep going up when I would sit in traffic. I took the car to the dealership for a diagnostic and they had me replace the thermostat. Well that did not work and I brought the car back to them. They were stumped and told me to try replacing the radiator. Well, the new radiator corrected the problem for me and I have not had a problem since.

mansurxk

iTrader: (14)

i dont see how a radiator would correct the program, unless the old one had a leak or is severly clogged, it just has to hold the pressure, if anything he should get a pressure test to see if the system is losing pressure somewhere, yeah the thermostat could be isntalled backwards

Jime

iTrader: (10)

You cannot install the thermostat backwards on a Maxima, its impossible.

On some cars yes, Maxima, no.

sharkulator

iTrader: (5)

I was told by a mechanic to bleed the cooling system of air in our vehicles you have to add coolant, then drive. Check the level, and keep on adding as necessary. You drive then check the level, I guess in the resoviour. Hope this helps.

d_hammmer

I replaced the rad on my 99 SE last summer. The car would overheat on hot summer days, but perform properly on cooler fall and winter days. I first replaced the thermostat but the car still overheated. After the stealership could not find the cause of overheating and wanted > $150 to test the rad core, I decided to change the rad myself ( with a new rad from Napa). It solved my overheating problem. The rad was also half the price that the stealership wanted for the rad.

Apparently in my case the rad was not cooling sufficently. I had the dealership flush the cooling system a year ago, but the rad seems to have either clogged, or otherwise failed

sharkulator

iTrader: (5)

You cant install the thermostat backwards. It comes with that metal housing and connets with 3 bolts that are in a triangle pattern. No way to install backwards. I know with city driving and the stopping and going is gonna put more strain on the coolant system but highway driving should not be as bad.

Chickan

iTrader: (12)

Since he said that turning on the heater drops the temp, his gauge is working fine, the car is just overheating.

In your coolant mixture, the "coolant" part of it is actually a misnomer, as it does not absorb hardly any heat, it is actually the water part that absorbs the heat off of the engine, the "coolant" part just raises the boiling point (so the water doesn't evaporate instantly) and lowers the boiling point.

Check and make sure your car isn't low on coolant, on my old 300ZX, I had a slow coolant leak that when the level was low enough, the temp gauge would start rising, and it wouldn't matter if I was on highway or city, so I'd blast my heater, let the car cool down, and then add some coolant/water in 50/50, and it wouldn't go back up.

If you have the system pressure checked, and it doesn't appear to be leaking fluid, have your radiator flow tested, could be clogged with junk.

Dubbya

iTrader: (16)

Could be as simple as a Thermostat, too. If your water pump went out and your car got hot one too many times your thermostat could be screwed. Replace it. If you ever have a radiator or water pump go out its a good rule to just replace the thermostat while your at it. Hope this helps

Ant96GLE

iTrader: (4)

Exactly, same as sharkulator said. I do have some technical abilities...


The only thing I can conclude is that my coolant isnt mixed with enough water. I'm going to check it out now since I'm heading to work and see if it needs some water, as far as I know it was full last time I checked. I'm going to do a complete flush during the weekend.

Chickan: Yes the guage is working correctly since it goes right back down when I turn on the heater. Its not low on coolant though, but I'm thinking that when the water pump was done, the coolant wasnt mixed properly and it was mostly coolant that was put in. When I changed the thermostat I took off the bottom hose to drain the coolant and I reused the same coolant since it was clean. I dont think my radiator is clogged, although I could be wrong. Yesterday I opened the radiator cap and turned the car on when it was cold. I could see the fluid moving around, so I do know its moving... I dont know how good a method that is though.

However, Thank You guys for all your help. I'll flush the system this weekend and run it... we'll see what happens.

mansurxk

iTrader: (14)

yeah sorry i was just agreeing with someone else who i thought mightve known what they were talking bout, i havnet changed it on the maxima yet, but i changed it on a few other cars where they can go in backwards, so my apologies, if might be stuck partially closed

first bet is to check the coolant/water mixture, we know your fans work, check the belt tension that drives the water pump, get a pressure and flow test, does it overheat in stop and go traffic?, doubt its your fans if it doesnt, check the radiator cap, take the thermostat out and do the water kettle test to see if it pops open all the way.

C MAX

iTrader: (4)

absolutley there is no way possible for it to go on backwards. ant give me a call maybe i can look at it, can't be nothing to hard to find.

Ant96GLE

iTrader: (4)

Yea fans work, thermostat is new.

CMAX, I'll give you a holla in a little while, I'm gotta get to work before I'm late.

ONce again thanks