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cold engine and no heat

3K views 30 replies 5 participants last post by  astro355 
#1 ·
It seems that my temp gauge does not go up that much. it tops out around 1/4. it used to go higher but not no more. i replaced the thermostat and fixed the wires for temp gauge. the heater, vent and defrost work on 3 and 4 but they only blast freezing air. every now and again I think it might kick a wave of warm air or maybe i get used to the cold. it leaks some coolant from time to time but there is no trace of where it goes. i am gonna try a heater core. that should fix my heat but what about the van running cold? any ideas on the diappering coolant?
 
#2 ·
Hello,

have you verified that you are low on coolant by checking the radiator?

does white smoke come out of the tailpipe?

If you feel that you are leaking antifreeze somehow, changing the heater core will not solve your problem, unless the heater core is leaking and that you would know since it would leak inside the van.

I would check your oil and see if you have antifreeze in your oil. You can also check your spark plugs. If you're burning antifreeze, the plug(s) will appear to be clean.

Also, while the van is running as warm as it gets, feel the hoses going to the heater core. If both of them feel cold, your problem lies elsewhere. If only one (or only part of one) is warm, you have a blockage in your heater core (or in the line). If both lines are warm, you're engine is not generating enough heat. Both of those lines should feel hot.

But in my armchair opinion, I think you have a blown head gasket. Loss of antifreeze and lack of sufficient heat being generated by the engine are telltale signs of a blown head gasket.
 
#3 ·
i will start one at a time. i thought that too but the oil is still oil not mixed into choclote milk. she still has plenty of power and never overheats.
i check the radiator often.usually every day or other day it is down the spout about alittle below the top of the rad. it smokes like the valve seals are gone and burns oil which it does. i mean now it smokes because the temp is cold and every car smokes til it warms up. it never has before just the oil smoke.
i havent noticed leaks inside. i tried the hoes a while back and one got real hot and the other one got pretty warm. recently i have noticed a miss but it's not that major. wouldnt blown h/g have loss of power overheating?
 
#4 ·
A blown head gasket (or warped head) can present a lot of different symptoms. But when you mention that you have no heat, the engine doesn't get very hot, and you are losing antifreeze, that just screams a bad head gasket. What happens in this type of failure is that compression is bleeding from one cylinder to the other. For example, say its happening to cylinders 1 and 3. The loss of compression in those cylinders will reduce the overall heat of the engine and cause you to burn some coolant. But what it wouldn't do is overheat or let the antifreeze mix with oil. Really, I've seen it before.

But again, I would start off with checking the plugs because if that's the case, the plugs in the "bad" cylinders will look different than that of the good cylinders. That miss you speak of may very well be the result of this.

Or on the hand, when was the last time you gave that van a tune-up? Old plugs that don't fire as well as they used to can also cause an engine to run cold. But they won't cause you to leak antifreeze.
 
#6 ·
90lownslow said:
i tuned it up last april when i got it. it doesnt get driven much so i havent added alot of miles. i thought that it might have been intake gasket but never went anywhere with that.
Ok, but with a leaking intake gasket, you get overheating. Your problem is that it runs too cold.

What kind of ignition parts did you use during the tune-up?

Have you pulled the plugs recently to see how they look? That would be a pretty good telltale to how the engine is running.
 
#7 ·
Lossing coolant and having a miss SCREAMS defective head or headgasket. :(
But, have you verified that the blend door is moving to direct the cold incoming air through the heater core. How do the radiator and heater lines feel? Top hose should be Hot to the radiator. Have you tried burping the system lately? Also the thermostat you put in could be bad, but my '92 runs below the 1/4 mark and its got great heat. :shrug:

Edit: Also make sure your heater control valve on the passenger side fender is opening and closing like it should when you switch from hot to cold on your heater controls from inside the Van. Those sometimes get stuck and don't allow warm coolant into the heater core. :D
 
#8 ·
good news good news my funding has arrived for the bad part it is really cold outside and my carport lacks a door and a heater. so i am gonna drive it for a while then maybe check out the pluggs. not right away i have learned to let things cool off. to burb the system ? take the cap off while its running and jack up or pull up on car ramps. so the cap is highest on system. is that right? the parts i used were autozone special. what does gm reccomend for replacement parts. pluggs wires etc. i pressure checked the radiator and it lost pressure. shocking i know right. i dont know anything about the blend door. or how to check.
 
#9 ·
90lownslow said:
good news good news my funding has arrived for the bad part it is really cold outside and my carport lacks a door and a heater. so i am gonna drive it for a while then maybe check out the pluggs. not right away i have learned to let things cool off. to burb the system ? take the cap off while its running and jack up or pull up on car ramps. so the cap is highest on system. is that right? the parts i used were autozone special. what does gm reccomend for replacement parts. pluggs wires etc. i pressure checked the radiator and it lost pressure. shocking i know right. i dont know anything about the blend door. or how to check.
Let's keep this simple, I wouldn't worry about the blend door. Losing coolant will ALWAYS result in lose of cabin heat. You should be using Delco parts for the ignition stuff. You may think you are saving money but the Delco stuff isn't that much more expensive and the money you'll save in gas leaves no comparison.

I would check the plugs IMMEDIATELY and really not drive the van until this is resolved. I can understand that if may be your DD but watering down the oil does your bearings, rings and other wear parts no favors. I would hate to see a leaking intake gasket turn into an engine rebuild. :2:
 
#10 ·
well i shoulve read this yesterday then. i went for a nice journey in her. after 14 miles the heat was warm not cold and not hot. today she was a little warm and i thought it might overheat. well it got just over half way on the temp gauge and then went back to a 1/4. i got some delco pluggs that are gonna find their way in there soon and some fresh oil. its not my dd but it should be. i know its not the best but she runs better when you give it to her ruff. YEAH I GUESS MY VAN IS A FREAK cuz when i take it easy she acts like she dont wanna go but if i beat on her she takes it and wants more. i will post back after i do the pluggs and wires. i had a 92 grand am that the head went. they are common for that. well it allways overheated and i had to constantly fill it with coolant. then it starting spiiting oil and then it reallly spit oil after it blew a hole in the block. i am not saying it is head gasket but its not like previous problems.
 
#11 ·
news flash :banana: all the old pluggs look the same equal beat and time for new ones. i didnt notice one that was clean or different from the others. the oil was black as night. not brown but needed changed. for some reason i think that the pluggs are gonna be easy and they never have been nor do they seem easier to change. i have some video that i will post up later. i can hear it outside still missing and it makes me wanna :banghead: . i started it with the cap off and the front jacked up. it started bubbling alittle and slowly overflowing so i put the cap back on.
 
#12 ·
90lownslow said:
news flash :banana: all the old pluggs look the same equal beat and time for new ones. i didnt notice one that was clean or different from the others. the oil was black as night. not brown but needed changed. for some reason i think that the pluggs are gonna be easy and they never have been nor do they seem easier to change. i have some video that i will post up later. i can hear it outside still missing and it makes me wanna :banghead: . i started it with the cap off and the front jacked up. it started bubbling alittle and slowly overflowing so i put the cap back on.
And then did you let it cool, add more water and start the van again with the cap off? You really have to repeat those steps until you can't add anymore water/coolant.

And honestly, I not sure I would worry about that miss until you get the coolant leak fixed. There is always a chance that the coolant leak is the cause of the miss.
 
#13 ·
this leak is killing me. yesterday i burped it but this morning it is low again. so isnt there more air in it now if it was leaking. i dont get this stuff. it makes sense if it is going in the oil but it is not brown it is black. the van likes to mark its parking spot but the oil used to never be low. but there is oil all over the carport.
 
#14 ·
i went to wally world lookin for a heater for my van.had one in the jeep a few years ago and it would be nice if i still had it. they show me a small heater that i dont think would heat the box it comes in. well i was thinkin about it and the special ed stock/ supersalesman of the year told me that his wifes car had no heat and he put drano in the radiator and now it will heat you out of the car. at first i was like wow that could work to unclog all the "pipes" so to say then my van was me a instant flashblack that it would probally destroy everything from the inside out. i dont know i am not a scientist or a smart guy but i didnt but buy the drano SHOULD I BUY?
 
#16 ·
not having any luck so i thought about just replacing parts. i got a radiator lined up for 50 bucks but then i decided maybe its not the radiator. so seeing how intake gaskets are ONLY $12.00 i picked up some of thoose and sometime they will go on. i know it is gonna be a pain but i am gonna research it and see if there is any tips.
 
#17 ·
Are you still trying to get heat or trying to find a leak?

Have you tried a pressure tester from like Autozone? Its on their rental program it goes in place of the radiator cap...its got instructions with it...maybe you'll get lucky and find a leak?

A radiator is going to either be clogged or leaking. It will never cause no heat......if anything it would cause it to overheat from being clogged and not properly cooling the fluid or leaking all the fluid out.

How are your radiator hoses? One should be hot and one should be much cooler. The top one shoud be hot/warm. You should also check the heater hoses to see if they are getting warm.
 
#18 ·
the hoses check out ok. i pressure checked it a while ago and it lost pressure bc it should hold 15 lbs and it didnt. the rad has some crusty nasty stuff and i wanted to replace it but it can wait. I HAVE A BIG QUESTION. while the van is running and you take off the rad cap. what happens? i always heard if it shots out then head gasket is blown. any truth? i know there is pressure built up but mine flows over and shots out then when i refill it up it oozes back out again.
 
#19 ·
Forgive my frustration here but you really seem to be going in circles here. When you attempted to fill and burp the cooling system, did you just do one round of it or did you repeat all of the steps until you couldn't get any more water in it?

The steps:

1-jack up the front of van (block the rear wheels)
2-remove radiator cap
3-add as much water as possible
4-start van
5-wait
6-once the cooling starts to overflow from the radiator, reinstall the cap
7-turn off the van
8-wait for it to cool
9-once cooled, remove radiator cap. If you can add more water, go to step 3. If you can not add more water, you are done.

Second, if you really think there is a leak, you need to pressure test it. If you KNOW that the radiator leaks, replace it. If you know of any BAD parts, you MUST replace them before you can do anything else.

When using the pressure tester, you are looking for two things. First, does it hold pressure? If the answer is no, the next thing you need to look for is where is leaking. You should be able to hear a hissing from where its leaking. You may hear the hissing coming from the under the doghouse, the throttle body, the exhaust, the hoses or water pump, radiator, heater core hoses, etc. But if its leaking, for god's sake, find the leak.
 
#21 ·
i got some news or a update. I didnt know where to post so i figured i would just continue on here. after further inspection to radiator and hoses are clogged with ? radiator stop leak or who knows. i went to the parts store for some carb cleaner to check for a intake leak. well it was missing and backfireing the whole way home. wasnt far but it still took a long time. then i pull in the drive and cant get it in the garage so i will park on street right. well it wouldnt stay running long enough to make it to the street so i just creep back down drive. well after starting it 100 times the starter broke. then it sat outside in the snow with a bad starter. not wanting to buy a new starter if the motor is junk i got a junkyard str and put her in. well i notice a rattle that is hopefully the piece of starter that broke. but she is running and sounding like norm. then i move her and notice a bad leak. thinking it is oil i shut her down and look for the leak. cant find then i notice it is break fluid. i just ran all new rear lines wtf. forgot about the front ones right well now they need replaced. so the motor isnt blown and i removed the piece of starter and no more rattle THEN I FIGURED THE intake needs done and now is a good time to start. so i have the intake soaking in oven cleaner n gonna clean everything up and put it back together. i isnt gonna happen over night but i have some pics comming. sorry to blab on about this forever.
 
#22 ·
90lownslow said:
i got some news or a update. I didnt know where to post so i figured i would just continue on here. after further inspection to radiator and hoses are clogged with ? radiator stop leak or who knows. i went to the parts store for some carb cleaner to check for a intake leak. well it was missing and backfireing the whole way home. wasnt far but it still took a long time. then i pull in the drive and cant get it in the garage so i will park on street right. well it wouldnt stay running long enough to make it to the street so i just creep back down drive. well after starting it 100 times the starter broke. then it sat outside in the snow with a bad starter. not wanting to buy a new starter if the motor is junk i got a junkyard str and put her in. well i notice a rattle that is hopefully the piece of starter that broke. but she is running and sounding like norm. then i move her and notice a bad leak. thinking it is oil i shut her down and look for the leak. cant find then i notice it is break fluid. i just ran all new rear lines wtf. forgot about the front ones right well now they need replaced. so the motor isnt blown and i removed the piece of starter and no more rattle THEN I FIGURED THE intake needs done and now is a good time to start. so i have the intake soaking in oven cleaner n gonna clean everything up and put it back together. i isnt gonna happen over night but i have some pics comming. sorry to blab on about this forever.
Thanks for the update. Oh, and by the way, we like blabbing. It's almost as good as pix. Jim
 
#25 ·
i was trying to just copy them but it didnt work so thanxxx to photobucket here it goes
this is where she sits now

look of inside do you know what happened to my seats i cant sit on that

intake covered with oven cleaner it helps alot




this is where i had to replace the starter so i could move it.
 
#26 ·
i took out the heater core and that son of a gun was cloogged shut. i tried to rinse it out but my whole system is filled with some stop leak lookin stuff. so i am gonna flush and replace some things and hopefully that will clean her out
 
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