I have little to no heat. I have been posting almost every thread about heating issues and I still have not gotten any answers. can someone please tell me exactly how to do a few things that might help my heating issue out.

1st, is there any how to's about changing your heater core? if not can someone thats done it before just explain a little what they did to replace it. If you have pics that would be awesome

2nd, is there a how to about flushing your heater core? if not can someone explain exactly how to do that?

3rd is there a how to on changing your Thermostat?

can someone tell me exactly how to drain all of the coolant out and replace it with new coolant?

I just want to get this heating issue taken care of. any information that anyone has on fixing the heating problem would be awesome. if I forgot something that might effect the heating and need to be replaced tell me about it and tell me how to fix it.

Thanks for your help

 

Buy Chilton's manual, answers for u are all over the forum, just read down there...

1. Why? Does it leak?

2. Take in/out tubes off from engine, hose water from garden hose through...

3. Chilton's. Just bolts off, clean, add some gum, replace new thermo, close. [if your dash gauge goes halfway during drive, no need to replace.]

 

just flush ur heater core, cooling system and check for any leaks. I did that and heat came back... and then i just took out the relay from my A/C since it was constanly working and blowing cold air thru front grilles, but warm air would come through windshield/leg warmer. so yeah, try all those, should help

 

actually the cold air blowing through the vents is usually because the fresh air lever is on. The lever beside the AC controls is use to allow cool air from outside to blow in when you have the heat on. A lot of people do not realize this but it is in the owners manual if you have it.

Of course yours may have been a different problem.

 

u mean the lever thats next to the clima control that goes up and down for hot/cold air... yeah that one was down and there still was cold air blowing... now that i removed the relay from the a/c, its hot in there! haha

 

About cabin heater valve, J30 -93:

Its located on engine bay wall, under the hood. It gets it operating pover via vacuum tubes from engine(check if leaking). It is electrically controlled (check its coil resistance and that it gets its control voltage). Open and check that it is mechanically operative.

 

I will check that out. I could see that being the problem because when I am driving on a highway I have little heat but when I am driving in town and in traffic I have no heat at all. the vacume could be running while Im driving and not running when I am not driving. I dont know, its just a thought.

thanks for the ideah. I will check that out.

if anyone else has any ideas or has fixed their heat tell me. Im going to have to do something soon because we had our first snow yesterday

 

Really obvious post here but mine does the same thing (heat perfect on the highway) and just cold air in traffic,it was because my coolant level was low,It doesnt have to be down much either,I only had to add about a litre or 2 and it was fine again.

BJ White

 

well I just went yesterday and had my coolant system completly flushed and I still have no heat. my engine temp goes half way up and stays there when Im driving so I dont think its my thermostat.

does this mean that I am going to have to change my heater core

 

BTW, radiator takes "flesh" coolant very slow (after drained). so give it some time and keep adding (intervals of 10-15 minutes should do).
and YES - check coolant level.

 

I just had my (RUSTY )coolant system flushed, and a switch in the dash replaced. Its so much nicer to drive without having cold air blast my fingers and ***** while I'm trying to run hot air out the defrost.

 

My max is working and temp never goes beyond halfway. Probably your thermostat is ok - anyways relative cheap to change.

If u flushed the core, and water came through, your core is ok. To test that u get fluid from engine, loosen the tube (a little) near the valve and verify that -engine running- the pumped coolant comes out from the engine (from thermostat block assy tube). If not, that part is blocked.

Check with your hand if the tubes at the core are hot. If the in/out tubes are hot, water reaches it...
Then the air ctrl flaps guiding air are not properly set (broken loose?) and air does not pass through the core. Check out the wires(stick) and how they move the flaps...

 

ok heres what I did. I went out and flushed my heater core. I had a little crud come out but not much. I went and drove my car for about 10 minutes to see if it did anything. I now have "ok" heat that come out of the vents but I only have it when Im driving. if at any time I am stopped and my car is idoling only cold air will come throug. but the second that I accelerate I have some heat again.

what else is there to do now besides replacing the heater core? do you think it could be something else besides the heater core?

Thanks

 

Heater core is one 'big dead box', it does not balloon, jump, rotate when u rev. So if its ok once, its always.

Coolant is boosted, running around faster on higher revs = more heated coolant flows to core. That heats the incoming air. U get constant coolant flow to core if:
- if coolant level ok
- if no air [gas bubble blocks] in system
- tubing/valve ok
- pump is ok
- thermostat is ok

Pump is rev dependent. If pump rotator blades are corroded, at idle flow is poor, revving gives better output, but still lacks...

I have some problem collections in my site but read first THE Maxima.org:
http://forums.maxima.org/showthread....=1#post3499240
http://forums.maxima.org/showthread.php?t=361759
http://forums.maxima.org/showthread.php?t=362106
http://forums.maxima.org/showthread.php?t=363118
http://forums.maxima.org/showthread.php?t=360258

 

you have an 89, that means you need to jack your front end up and bleed the air out of the system. right now you probably have some major airpockets. which, believe me, will cause the problem you are describing

 

ok I remember someone saying something about jacking the car up and bleeding the coolant. how high up does the car need to be? how do you go about bleeding the coolant? any help would be great!

 

It has to go so up that all air bubbles get out...

Fishermans wisdom for Peters catch: dont run, think as u were a fish.

Think about the multidimensional system with small&large tubes, curves, crimps and cramps: small bubbles wisped by u pump, how they gather for their concerts? What are their physical properties? How to lure 'em out? Like u belly after coke, i scream, choko late bubbling burps, howto get pain away?

U dont stop to read too much of the info offered... Read, questions abate... all info has been already given. For bubbleshooting, that is.

 

the car is supposed to be jacked 39" up in the front. (good luck)
with the engine running and the radiator cap off, keep adding antifreeze for about 15-30 minutes.

 

Yea I made a post about a similar issue I was having a few weeks back... My heat would still work, but on occasion it would start pumping out cold air for no apparent reason (the engine was already warmed, and I had even been driving the car for a while so the heat should have been hot.) then it would start working normally again. It was weird and very inconsistent. Then, last week I got a tune-up and also had them flush and fill my radiator - that seemed to work because since then my heat has been working GREAT (as it used to and should be) without pumping cold air at all!!!! HoOrAy!!

I would suggest checking the coolant first and foremost!

 

Sorry Maximaboi - I didn't see the post where you said you already flushed the coolant...sorry i couldn't be of more assistance!

 

I purchased my 89 Maxima from a guy that came from California. I'm guessing that 99% of it's life the heater was never used. That means the restrictor that mounts on the firewall was not allowing very much coolant to pass through the core and thus letting alot of rust settlement from the block and byond to rest at the bottom of the core. I'm betting it's still got 25% blockage after me flushing it with water and compressed air 5 times over the last few months. Every time I blow it out and into a bucket it's got alot of setement. That's my problem and just regular flushing won't get much out. Compressed air... then fill core with fluid.. blow again with compressed air .. fill with water again.. air/water air water.. That's just what worked for me. I've only ran into a problem with air bubbles in the system when I completely drained the radiator. The way I fix that problem is fill the system through the top radiator hose..that way it fills the block first then flows to the radiator taking the bubbles with it. I've had to do that on a LT1/S10 Swap I did several years ago with that wacky reverse coolant flow BS.
E-mail me if you need further help!
Scott~

 

well I have some good news. while I was driving today I went to reach for the heat controls to turn the heat down because I was getting hot! then I realised "hey Im getting hot in my car!!! lol" my heat is working just fine now! it runs just as hot when Im at idol than it does when Im driving.

I didnt do anything other that what I said I did in this thread. I guess I just had to drive my car a little longer last night for it to start working. but it all works just fine now. I hope it will stay this way and not go out on me.

 

maybe it finally burped itself