heat's not hot enough!

[maroman88]

what the hell! the heat in the 95 SUCKS! all my third gens have gotten BOILING hot heat even with low temp t-stats. the 95 just doesnt heat up, even after city driving for a half hour it still leaves much to be desired. you think something might be clogged on the way to the heater core? i have no idea where to even start

[maroman88]

leading me to think the t-stat may be stuck open? car also takes a while to warm up

[BonzoHansen]

Start with basics. Low water level is usually culprit #1. Also, what is the temp gauge telling you?

[maroman88]

level is right on target. temp guage doesnt get past about 190 usually and i just checked the guage against my scanner and its on target

[alamantia]

Reverse cooling FTL, if it were me, I'd put a stat in it and while your doing that flush out the heater core with the garden hose...

EDIT: Dont forget to use the bleeder valve to get all the air out of it too..

[BonzoHansen]

..yeah, air in the sysem can cause all sorts of weird cooling issues. T stats are cheap, try it. Your fans aren't running 24/7 are they?

[JL8Jeff]

My 93 wouldn't heat up much with the 160 t-stat. If you look at the heater lines with their 90 degree bends, it explains why the core gets blocked up. The flow is minimal at the core so you need to backflush it. GM used that cooling system sealer that also tends to block things up in some places. I had to backflush my 93 every year before winter started. I disconnected the hoses at the water pump and with a garden hose tried to force the water back through. If you want to do a quick check, with the car warmed up, grab each heater hose and if one is hot and the other is not, then their is no flow through the heater core.

[maroman88]

nope the fans arent always on, ill do the t-stat and flush the lines like jeff says :)

[deadtrend1]

yea, i need to flush mine out again. Heat is non existent in the car again ..:willy:

[maroman88]

k, i checked the t-stat, its good, put it in boiling water n it opened

i flushed the radiator, the old cooolant was very watery and brown. i have to do the whole system still

i shot both lines coming out of the heater core thru the fire wall with a temp gun, one was 145 and one was 112 degrees

[ar0ck]

i flushed the radiator, the old cooolant was very watery and brown. i have to do the whole system still


Sounds like the previous owner mixed dexcool with regular anti-freeze. I would def have that flushed.

I have a 160* in my car and it does take a little bit longer to warm up, but give it a nice 10 minute idle in the driveway and the heat gets pretty dam hot.

[johnjzjz]

i don't know on the new Dex type but the old type anti freeze if their is too much meaning -50 mix the heater core cant get the temp transfer needed to get hot for correct heat -- an old problem -- jz

[maroman88]

thanks everyone! i now have the hotest heat EVER!

i flushed the heater core and blew it out with the air compressor and TONS of rust n crap came out of the pressure reducer on the lower hose

also changed the t-stat since i was in there

[JL8Jeff]

At least you did it before it got real cold out. Those hard lines are stupid with all the sharp bends which reduce flow. It was a pain backflushing it every year in my 93, but it had to be done or I had no heat or defroster.

[String]

thanks everyone! i now have the hotest heat EVER!

i flushed the heater core and blew it out with the air compressor and TONS of rust n crap came out of the pressure reducer on the lower hose

also changed the t-stat since i was in there

How did you go about flushing the heater core? did you just flush the whole system with the heat on or something? I have the same problem with my 89 camaro. The heat is maybe compareable to a warm breath of air. thought about just replacing the heater core after having the system flushed a few times and still no luck.

[deadtrend1]

How did you go about flushing the heater core? did you just flush the whole system with the heat on or something? I have the same problem with my 89 camaro. The heat is maybe compareable to a warm breath of air. thought about just replacing the heater core after having the system flushed a few times and still no luck.

flushing the heater core is more common on 4th gens then 3rd gens for some reason. Dexcool would be my guess.

On your car i would flush the whole system. Theres a plastic valve on the passenger side with hoses going into it. That controls the antifreeze flow by a vacuum line to aid the ac. I usually by pass it cause I had one explode on me. That could be a problem too.

edit:

Should ask what degree thermostat do you have in there and what is the guage reading on your dash.

A bad heater core will usually leave its mark of steam on the windshield and/or antifreeze on the carpet.

[Knipps]

i need to flush my dexsludge out at some point.. i went the winter without heat
don't think i want to repeat that

[String]

Should ask what degree thermostat do you have in there and what is the guage reading on your dash.

A bad heater core will usually leave its mark of steam on the windshield and/or antifreeze on the carpet.

Its a 160 thermostat. I have flushed the system a few times but hasn't really helped. even with the old 180 stat it wasn't hot. the temp gauge is all jacked up now and doesn't always give me a correct reading but when it did work (or when i thought it worked) it always said 220.

[String]

thought maybe the heater core was completely clogged because 2 years ago i had an issue with the internal tranny cooler bursting in the radiator and made everything all sludgey. so i got a new radiator and an external trans cooler to keep it from happening again.

[Slo86Bird]

my truck hasnt had heat since i bought it....the mechanic says its the heater core but he wants 1400 to change it and u have to take the whole dash apart to change it so i can live with no heat but i need it lol

[JL8Jeff]

The LT1 cars have heater lines with 90 degree bends and then add the dexcool issue and the core will clog due to low coolant flow. If you backflush the coolant lines and core from the water pump on back it will help. The real solution is to ditch the factory 90 degree lines and put in heater hose with a nice straight shot. As for the 3rd gen, I have no idea what helps because I've never owned one.

[String]

the weather should be getting nicer soon so ill just put it off some more and wait till september to worry about it again. got some other stuff i need to fix first.