2002 Altima Heating Issues?

[RJ45]

Lately I have been having an issue where if I am sitting idle (stop sign, red light, etc.) the car pumps out air, but no heat to go along with the air so its just cold air... now once I am driving or pushing the gas at all, heat starts pumping/flowing again. This just started recently, not too sure what the issue could be. All fluid levels have been checked and are fine, no issues there.

The car is a 2002 Altima 2.5SL

Thanks!

[le_ryan]

... sounds like a clog in the heater core, hence once you hit the throttle the coolant gets pumped around at a higher presure than without throttle.Try a coolant flush if its needed, that might help.

[RJ45]

Will give a coolant flush a try, thanks! Just out of curiosity... is this something normal? or is it because of the weather we have been having lately (-48 degrees celcius!). Also are there ways to prevent this from happening again? (if this actually is the problem)

Thanks!

[le_ryan]

depending on the mileage, it is a normal thing, another thing that it may often be is the thermostat being stuck open or shut, id knock that out while your at it, $7. part.

[garthog]

have you figured out what the problem was? mine is doing it now too. i just had a coolant flush but it's still doing it. by the way... where is the thermostat so i can swap that out?

[RJ45]

I still haven't figured out the problem yet, did a coolant flush as well and no luck with that.

[Spddracer]

Yo

Lately I have been having an issue where if I am sitting idle (stop sign, red light, etc.) the car pumps out air, but no heat to go along with the air so its just cold air... now once I am driving or pushing the gas at all, heat starts pumping/flowing again. This just started recently, not too sure what the issue could be. All fluid levels have been checked and are fine, no issues there.

The car is a 2002 Altima 2.5SL

Thanks!

guys should realy make this a sticky. 02-06 alitmas/maximas have big problems with air in the cooling system/heater core.

This is what cause no heat or low heat output at idle conditions.

You have to raise the front of the car, bleed the air out with heat on high while raising the engine RPM>

To fix!

Cool engine Remove radiator capPlace paper clip in top of radiator neck to prevent cap seal from sealing.Reinstall capTop off radiator overflow tankRemove bolts from overflowHang O-flow tank from hood latch striker as high as poss. Raise front of car aproxx. 20" from ground to bottom of bumper.Start engine and hold RPMS at or around 2500-3000 While doing so periodically squeze upper radiator hose and heater hoses for about 20mintues. May take longer. Let idle and see if heat stays hot

If it does your done, If it cools off at idle you need to repeat process until it stays hot,

A tell tale sign of air in the system is a sloshing/water rushing noise in the dash after idle and reving engine slightly.

[garthog]

whats the deal with the paper clip? i don't understand where to put it. thanks for the advice!

[RJ45]

Wow I need to try that out, thanks for the advice... what mainly caught my eyes was this:

A tell tale sign of air in the system is a sloshing/water rushing noise in the dash after idle and reving engine slightly

Thats EXACTLY what I have!

Also, when you mention topping off the overflow do you mean to the max level or all the way to the top? as currently mine is a little bit over the max level.

[chrisjm00]

Hey. I think I have a fix to your problem. I just recently got an 05 altima and it was doing the same thing that you described. I changed out the radiator cap and now I have heat at idle. You should try that. It worked for me.

[dblink]

just worked on my daughters 2005 altima with same heating problem. we changed the radiator cap first with no luck then went for the thermostat. funny thing I found out is there is two thermostats!!!! yes one on the upper radiator hose and one on the lower radiator hose. my daughter has informed that the problem is now gone.

[billyballz]

THANX FOR THE ADVICE. I JUST FOLLOWED ALL OF THE INSTRUCTIONS AT A FRIENDS HOUSE AND NOW MY HEAT IS SO HOT IT'S BURNING MY FEET!!! IT TAKES A LITTLE TIME, BUT SO FAR SO GOOD. I'LL KEEP YOU POSTED IF I HAVE THE HEATING PROBLEM AGAIN

[rf]

Where does the paperclip go?

[Cold_Zero]

Other causes of low heat:Low Coolant level (easy to check)Thermostat that is stuck. Might try Spddracer's fix first, since ripping out the Thermostat is harder than his fix.

[2008CodeRedCoupe]

The paperclip is not necessary. If your goal is that the radiator cap doesnt seal, then why put one at all.

[utonium]

im also having the same problem for a while now with my 2002 Altima 2.5SL.

im not much of a mechanic at all, can i just replace the radiator cap myself? or is it complicated?

[utonium]

any update?

[utonium]

UPDATE

fixed my heatin prob,i did what someone mentioned, i flushed the radiator and now its HOT!!!! im freakin sweatin at 2nd setting. hope tis sorta helps people that run into same prob

p.s.

i also changed my air filter (not sure if it helped in any case)

[Prntguy]

I have had this problem on and off with my 2003 Altima 2.5S. My mechanic told me that it is an air bubble. To rid your sealed system of this you must jack the front of the car up to 20 degrees and it will come out. Don't forget to put the rad cap back on before you lower and start your car.

[blownb310]

The paperclip is not necessary. If your goal is that the radiator cap does'nt seal, then why put one at all.

The reason you use paper clip [or in my case an extra cap that I nuetered] is so that you don't leak coolant all over the shop floor while you're bleeding the system. This way all of the overflow gets recovered by the car's plastic expansion tank. Much cleaner way to do things.

[jwerty1]

The root of all this no heat trouble.....most likely a headgasket leaking, not bad enough to ever smell it, see white smoke, and usually not enough to overheatI've fixed several of these now, air bubbles are there because, you lost coolant somewhere and it didn't get replacedbleeding the air out of a coolant system with no leaking headgasket is easywithout replacing the headgasket, you will probably bleed out the system once a year, if it were my car and didn't have any driveability issues or CEL's I would just bleed it out everytime, but if you really wanna fix it, you need a headgasketdo a cylinder leakdown test, or even simpler, get the engine hot, then pull out the plugs and let it sit, shine a flashlight into the cylinders after a while, see fluid? its coolant

[evenplayn]

Careful, this was the first sign that my engine was shot! As jwerty1 mentioned, it was a leaking headgasket which was because of a blown pre-cat that destroyed my engine.

[shynepo3]

I'm having a similar issue, but even when the car is revving on the highway, the heat is lukewarm at BEST. I use to hear the coolant slushing in the dash, but no longer do so. Also, it use to take a really really long time to get the heat working, but now, it does not come on - it just gets slightly warm when i get on the highway, so i assumed it was the engine heat i was getting.

I'm clueless when it comes to doing car-releated things, so will trying the fix above be worth a shot? My mechanic replaced the thermostat, but it didnt help. I wll change out the radiator cap next. Any other things I should try before doing this fix? should i have the coolant flushed? my mechanic suggested putting in a rad flush bottle when the engine is cool, and driving around for a week. then come back and he'll flush it out.

pls help, i'm close to just selling the car, as it gets very cold here in canada and i can't go a winter without heat.