clentonz

This is for my sister's car, and she was recently driving down the highway(not paying attention); and overheated the car. She limped into pep boys smoking/steaming, and they replaced the thermostat.......This is from what I know, I was out at school and just got the gist of it. But since I may be inheriting the car, it is kind of my problem . ....girls who don't take car of their cars

Anyways, she said that after the overheat and thermostat replace, everything is all fine; except for the heater...The A/C works fine, and the heater blows air, but no warm air at all since the incident. ***The heater DID work before the overheat***just found that out....

I can't really think of a reason why this would effect the heater directly, and nothing else? But I ....they are about to take it too the mechanic(I DON"T TRUST HIM, but my dad does) but he seems to charge a arm and a leg every time we bring in the SC4......Called him, and w/o even looking at it, he said" eh its probably the heater core, and will be around $2,000.....thats pretty much half as must as the car is worth

Anyways, If any of y'all could help us out with this; that would be greatly appreciated

In the mean time, I am going to be searching the boards....and have been reading up on the heater control valve; but I don't know if the heater issue is b/c of the overheating or just simply going out.

BSC300TT

First things first, Have you checked coolant level? My heater didn't work and I found it to be a vacuum hose on the water solenoid that allows water to flow to the core. Sorry if I butchered the terminology. It was located on the firewall passenger side. there should be a water inlet and an outlet to the firewall along with a vacuum connection. good luck

clentonz

Alright, I just went out there to see what is going on with the heater control valve...and the coolant is not too the max, it is about 1/2 low from overflowing(after putting the cap on)....so I need to fill that up a little bit more.

Where is the vacuum hose located, in comparison to the heater control valve?(I will take some pics here in a min, and try to get them up as fast as I can)

But there were some things that I noticed. It was not true that there was no heat coming out with the heater...sorry about that, I was told the story; and then went out there to see what was really going on....

When the car is at normal operating temperature, and at idle, the air is quite cool; but when I put my foot on the gas and bring it up to about 2k rpms....warm air starts to come out?? I could keep my foot on the gas and hold it at about 2200 rpm's and get some "warm" air....but once I let my foot off; it would get cold again

.....So I found the heat directly correlated too the engine and if I was giving it gas or not?

I did check the heater control valve too see if it was working, I turned on max cold, then turn it up to the heat....and a slight turn down from max cold, I could see the heater control valve moving....
Max Cold= Solinoid pushed up
Max Hot= Solinoid would go down, and slight bounce up(1/4inch)...Don't Know if that going all the way down; and then back up a tiny bit has anything to do with it?

So, the heater control valve IS working.....this could be a bad thing, and mean that the problem is the heater core$$$

***One more thing, while bringing it up too about 2000rpm-2500rpms the engine/car would make a shaking, weird noise(can't descide it, but def. not normal) it would vibrate the car; and sound terrible.....I don't know if this has anything to do with the heat...I just noticed that, and have never felt that before; feels sooo rough at those certain rpms..***

So, I'm going to go fill the coolant up too the very top, and try to get some pics.

In the mean time, I will try to do some more research; and get those pics up (so my dumb azz can know what parts/hoses y'all are talking about)

Thank you all so much for the help, I really appreciate it...sorry for my typing/English errors....my fingers are frozen...thanks guys

...WOW, sorry for such a long post; just trying to be as detailed as possible

neurocity

iTrader: (17)

Moved......

clentonz

A little update, I filled up the coolant to the very top(all this occurred at idle), and it defiantly helped warm it up a bit more. So I'm sitting there, thinking that all is well; and I just saved myself a lot of $$$ w/ just a little more coolant....when I desided too take it out for a drive...(the whole time, the heater was with the a/c and non circulating position)...when I went driving around, it started getting cool/colder again???

And now am thinking too myself that I was getting the heat from the heat of the engine itself; now when I drive, the cold air blows that away; and I'm getting the outside cold air. (it would get colder when I turned on the heater A/C and circulating buttons)
heater control valve works....
Coolant filled up to the top.....
I DO get heat, especially at idle sitting there.....
But it gets colder when I drive, but not cold cold; like I have NO heat at all, and feeling freezing air
The heat dissipates even more with the A/C and Circulating on

These are not syntoms of me needing a new heater core are they?

Any info would be greatly appreciated, (I have a appointment set up w/ the mechanic tomorrow, and I know its gonna be expensive no matter what)

Thanks everyone, Happy Holidays

93twintrbo

iTrader: (1)

I highly doubt you need a new heater core. If it was leaking, then yes. If it was clogged, you can back purge it and clean it out. My guess is that the heater control valve is not fully opening, or you have a pin hole in the vacume line.
Try this, wire the heater control valve to the open position. See if that solves our problem. If it doesnt, then it could be a blend door issue.

Lawrence

BSC300TT

I was thinking that or he mentioned a rough idle now. could possibly be a blown head gasket. check the coolant level again and look at the oil and see if its cloudy. might have warped the head.

BSC300TT

also check the water pump. with the car cold take the cap off and watch the water as the car starts to warm up"make sure the heat is on". once the thermostat opens you should see the water start to flow. If it stays still then I would start there.

Spooled

iTrader: (1)

did you try topping off the coolant with the heater running? try raising the front of the car a little bit, (even parking in an inclined driveway works), remove the radiator cap, start the car, and add water/coolant (toyota red coolant) with the heater running on high. Sounds like you just have some massive air pockets in the coolant system. Do this for a good 10 mins, then over fill your coolant overflow resevoir, and drive the car. Even before you drive it you should feel heat coming through the vents. Keep an eye on the temp. gauge during the process.

clentonz

I really really hope that I don't need a new core, that would hit the bank HARD. If the heater core was broken....would I be getting ANY heat at all?

How do you purge it? I've been reading about how air in the system could be the cause of the heater issue; and that on 95' SC4s you could purge the air through the front?

This all started b/c my sister was not paying attention or whatever, and ended up on the shoulder with smoke/steam coming from under the hood....I'm not really sure of the extent of the overheating, this is all just from what my sister/father has told me.

I just really want to get this heater thing fixed w/o spending an arm and a leg; hopefully free .....
-just recently spent $1200 on the steering system/maintenance....
-Someone tagged the passenger side of the car(not our fault), insurance dealt with it; not that bad but still....
-And now overheated it, my sister took it to Pep Boys and they threw in a new thermostat; but the extent of the damage has not been assessed yet....
- Now the heater, with mechanics quoting a $2000 fix if the heater core is dead; because they have too take out the whole dash etc......

^^^And this was all within 2 months, and if it really is the heater core; that's $3200 put into a 1995 SC4 with 170k+ miles on it....that is probably worth 4-5K after this issue gets resolved and I fix some other little things(FR speaker out, 1-2 exterior lights)

Sorry about the rant guys, its a very long frustrating story that I'm not going too put y'all through; It just really makes me mad when people don't take care of their cars.... Especially on a car such a (could be), very nice Lexus.

Anyways, thanks 93twintrbo, I appreciate your help I will defiantly look into that tomorrow. If anyone else has any info/help on this issue; it would be greatly appreciated. Thanks guys, some very kind/helpful people on this board

p.s. again, sorry for such a long post

clentonz

Its like 4:00am, but I plan on doing this in the morning....Start the car, with the heater on, and with the water cap off; the water flowing means that all is good right? If not, then this could be the issue?

Ya, I did top it off, but the engine was off as well as the heater; I parked the car at a slight incline(Slight enough to maybe roll back, but not that steep at all....Texas lol) and I was using the regular green 50/50 General auto antifreeze....not the Lexus red...Do you think that the Lexus coolant would make a difference? All I did was top off the coolant w/ regular, car off, no heater, and basically no incline....everything opposite from what you said lol. I will defiantly try this tomorrow....I will do some searching on replacing the engine coolant so I can use the Lexus coolant. I really appreciate all of your help BSC300TT...whether it works or not...thanks bro

This defiantly what I didn't want to hear, could that happen from overheating? I'm gonna overflow that coolant, just to make sure. When I check the oil tomorrow, what do you mean by "cloudy"....like lighter swirls mixed in with the regular color? Sorry, I'm kind of new too this. I REALLY hope it isn't a blown head gasket...so if it is cloudy, than more than likely it is? Or at least something is very wrong with the engine?

Thank y'all soo much for the help, you do not know how much I appreciate it. Once I heard about all these problems from my father/sister, and about how they were going too the mechanic, I told them too hold off for a bit....lets see what the guys at CL have to say about it first. Thanks everyone

BSC300TT

no prob man. yea instead of a clean clear or depending on mileage black oil, it will be cloudy like tons of little bubbles in it. It usually looks like a chocolate milk shake. And yes water flow is good and do like they said let it run and keep over filling it. Personally, I don't see why it would matter what color your anti freeze is, but what ever. That's not going to fix your problem. If you are worried about it then fix the problem cheaply and then go put the good stuff in it. But it sounds like you still have air in the system. Rough idle...I don't know. what part of Texas are you in? I'm in the Dallas area.

kyoso23

If it were your heater core, you would probably have had coolant on the floorboards. You are losing coolant somewhere, and it really sounds like a headgasket, due to a warped head from the overheat or a faulty water pump. Do not drive the car obviously until you get this sorted out. Check the oil like stated above. If it looks normal, top off your coolant with the heater set to hot and the engine running. Slowly top it off until it has clearly pushed all the bubbles out and is circulating good and starts to overflow. You can also check the coolant for oil. Once you've identified the problem, drain and refill the coolant with the right stuff. Good luck man.

clentonz

Appreciate it guys,
About to go out and do this now. BSC300TT, I'm located in the DFW area as well

Here goes nothing....

I'll let y'all know what happens.

pogoism9

iTrader: (1)

one of the first things that happens when you blow a head gasket (combustion to water jacket variety) is you airlock your heater core. Thats why you are getting cold air.