I can let my car warm up for 30 min and still won't blow heat until I start driving for a few minutes. Even at fast food drive throughs it gets cold sitting in line. The engine temp needle never changes from the normal spot. Anybody know what to do about this? Also about the transister for the blower, my 4th speed makes the whole car vibrate and 1 and 2 seem to work but weak. Will replacing the transister fix that? thanks

 

thermostat is stuck in the open position.

 

If we assume that the "normal spot" is in the middle, then the t'stat would not be the issue...
heater core?

 

It could be a water pump. Sometimes the impeller wears to a point where its not very effective. A friend with a '94 and high mileage had the same issue. It was OK when he was moving but when stopped it would start to freeze inside (frosty windows on the inside).

 

make sure you have a enough anti-freeze, and check the thermostat, if anti-freeze is flowing when the engine is cold replace it, it should not be flowing through the stat

 

I misread. Sound is right. Restricted core.

 

Thanks for the info. How do I tell if coolant is flowing through the thermastat when the engine is cold? If it is the heater core anybody know how to test it/ replace it? If its the tstat, I imagine I just buy a new one and swap it out, but the heater core I know nothing about.

When the car is driving the air just gets a lil warm not even hot. once i stop and idle it goes cold, especially now that its in the teens out there.

And yes by normal spot I mean the needle is always in the middle once it gets up there.

 

Would taking it to valvoline or jiffylube and having the colant system flushed solve anything? I've never had that done but have meant to for the past few years.

 

Those flushes use the engines coolant flow push the old coolant out and suck new coolant in. You want a reverse flow flush that goes backwards to the engines flow to push the built up junk out.

Let me ask you this though, before the heat plain old stopped working, did it get weaker? did your interior windows fog up and did you get a weird smell?

If your cars warming up normal its almost surely not a thermostat being stuck open. You could try those flushes at jiffy lube or whatever but you may end up just replacing the old heater core.

 

Last winter I thought it didn't get as hot as it used to, but only in the heart of winter did I notice. I never got a funny smell and even a month ago or so I could let the car warm up before driving with the heat on and it'd be warm when I got in the car. now it just blows cold air even when the needle is in the middle(fully warm) until i start driving and even then its only a little warm.

 

could not having enough coolant cause this like someone mentioned? I know that there is usually little if any in the resovior but its always been this way.

 

As long as your radiator is full the reservoir being empty shoudn't affect your heat. The only thing I can think of beside the heater core is maybe a problem with the electronic climate control?

Also, if its not hard to take the heater core out (never done it on a max some cars its easy some its not) maybe you could pull it out and look inside of it with a flashlight and decide whether or not its clogged.. if you can do it yourself it's a cheap job anyways and more than likely the problem.

EDIT:
This is not a winter driveway job, you need to remove the ENTIRE dash and instrument panel, according to alldata.

 

every time i've checked the radiator has been full, but I haven't checked in a while. I'll have to check that out. As far as the core goes, would cleaning it out work, or is this something that just needs to be replaced? I looked earlier in the shop manual and couldn't even find where it is in the car.

I have manual climate, but you're probably talking about the electronics inside.

 

Yes the heater core is buried under the dash, which is ridiculous. Some shops will have a powerful reverse flow flush system that might help your heater core.. most shops would tell you to replace it. It comes down to what you wanna do. You could do a flush and see if that helps, and then replace.

 

maybe i'll try a coolant flush cause it is way too cold to work in my driveway. anybody know how much it costs. and do you ask for a reverse flush? or are they gonna look at me like i'm crazy.

 

i just checked the radiator and i couldn't see any coolant in it so i added some till it got up to the top. i'm running the car now to see if it warms up inside ( crossing my fingers)

 

well that didn't work the temp needle got up to the middle and still no heat. the radiator was still cold to the touch, is this normal during the cold winter?


by the way, thank you everyone for the help so far.

 

the RADIATOR was cold after letting it idle, but the guage shows normal op. temps???
hmm...does not compute.....
does the upper radiator HOSE feel hot? Did you change coolant or had any part of the cooling system serviced recently. This new info makes it sounds like a giant air pocket somewhere.....

 

the metal part of the radiator was cold to the touch after the needle got to normal position in the middle. so i slowly twisted the cap off the radiator and i could hear the pressure releasing. I just added some coolant before idling so i wanted to make sure there was enough in there. I've never had the coolant system serviced in any way.

as far as the upper radiator hose, i didn't feel it.. if this is important i could go back outside let the car warm up and try again.

 

ok i just tried again and the upper hose gets hot, and the radiator between the cap and the hose gets a lil warm, and the other side of the cap on the radiator barley gets warm.

oh, and when i just tried the heat in the car the first second the air came out the vents felt warm, but then turned cold.

 

you sound confused. If you have a heater core problem, you may want to try the prestone super radiator cleaner since changing the heater core will be very costly. as for your last post, i cant understand what you are feeling. the radiator? the hose? what is the other side of the cap?

 

i'm feeling the radiator itself, the top of it on each side of the cap. and the upper radiator hose. i just noticed the radiator wasn't hot, maybe because its so cold outside, but i thought it gets hotter.

as for the prestone super cleaner, is that a cleaner you buy and use when you flush it yourself? would that be better then going to valvoline.

 

your rad should be cooler on one side than the other. One side should be hot however. going to valvoline is fine if they are going to backflush it (flush it in reverse) If the buildup is significant, i personally dont think that would even help very much but each situation is different. The prestone stuff is something you do yourself. the problem with doing it now is that you have to run it for about 3-6 hours but cant let the car get too cold (since it is the flush + water and that will freeze). Some people fear using the Prestone because they are worried about it causing leaks in old seals. If you want to try and backflush it yourself, you can disconnect the 2 hoses that run into the firewall. hook up a garden hose (if its not frozen) or one of those car wash spray nozzles and blast it through. Prob wont make it sparkling clean but will definately get out some of what is in there.

How long does it take for your car to warm up in the morning? (temp needle to reach the centre)

 

just starting it and letting it idle it takes between 5 and 10 minutes to get to normal temp. starting it and driving right away i'd say it takes 5 min at most. i have a flush kit i bought a few years back but never used. its too damn cold for that anyway so maybe i'll call valvoline tomorrow and see if they do the reverse flush.

 

1st of all a radiator flush will do nothing if your heater core is clogged, it will clean your cooling system to a point but not to the heater core, trust me I know, I spent 2 seasons of flushing to no avail with my clogged heater core. I guess it could depend on how bad it is clogged. Mine was extremely plugged.
1st thing to do is check your heater core hoses to make sure they are both hot. If they are then you have flow through your heater core and it is not clogged. If the lower heater core hose is cold and the top is hot then it is clogged, like mine was.The best thing to do is flush the heater core and see if you can break loose whatever is in there. Take off the top hose that runs to your heater core and dissconnect the lower hose as well. Take your hose and spray in the top hose and see if you have flow out of the bottom hose, if you do then you do not have a clogged heater core and your problem lies somewhere else. If you don't get flow then your heater core is clogged and will need to replace it like i did. It was a 10 hr job but my heat is amazing now!

 

i had the exact same problem on my max... the heater would only push out moderately hot air when the car was moving... if i stopped at a red light... den it would start pushing cold air again... i didnt have time to figure out what exactly was the problem... but 2 monthz later (last month).. my rad started leaking... so had to put a new radiator into the 95 max... new coolant.. checked everything... n jus turned on the heat... n strangely enough... the heat workz perfectly once the car warmz up... maybe this'll help..

 

great.. 10 hours geeze. well i'll see if a flush will do the job and if not, i'll have to just deal with it till it gets warm outside. hopefully its not clogged too much. thanks guys. i'll post back when i have it done.

 

again. Preston Super Radiator Cleaner. The on you have to run for a good 3-6 hours. If there is gunk in there, that should clean it (as long as it is not completely blocked up). Heat on high. Just remember not to let the water freeze (since it will be cleaner + water in the system and no anti-freeze).

 

maybe i'll try the prestone if the flush doesn't work. i'd rather have it done because then you have to dispose of the colant and cleaner properly cause its harmfull. thats def. an option before ripping the car apart to get to the core. running it for 3 - 6 hours, is that idling or driving or a mix? thanks

 

Driving. And when you said you were going to try the flush i thought you meant flushing it yoruself. Try a shop and see if they will backflush it. Smaller shops may be more willing. Whatever you do, dont wait too long and let it block up completely.