Heater Problem - '01 Eclipse GT

Hello, Group !
My wife started complaining about the heater in her Eclipse....said it doesn't stay warm....
Now, in the past, I've found that the V6 produces PLENTY of heat...too
much, in fact <g>...so I figured she was just whining because she's sick of winter.
I've driven the car the past few days, and she has a point...the heater seems to run fine when at speed or accelerating, but when you come to a stop, you can immediately feel the temp from the air vents drop off...can get down right cool if the traffic signal timing is long enough. I note the thermostat reading does NOT fluctuate...holds pretty steady....it's like it's something inside the car that's screwing up the flow of hot water to and from the engine.
Any suggestions on what to check, or should I turn it over to the hacks at the local Mitsu dealer ?
Dean....
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
I have the same '01 and I notice the same thing but only when the fan is not on. I know it's not really supposed to be that way but I have learned to live with it. If I'm too cold, due to the symptom you mention, I just turn the fan on 1 when I'm at a stop light.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Tom,
Your response made me think....ya know, it shouldn't BE that way ! The car used to have decent heat before...ours wasn't always like this ! I vaguely remembered we asked the dealer about this once before, when the car was in for service. I pulled my records from that visit, and it said the coolant level was low, so they added stuff and tightened all the hose clamps....it DID seem to make a difference, so I guess I need to check the coolant, although I'm pretty good at making sure the various fluid levels are okay...
Thanks for your response !
Dean....
Tom wrote:

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Sounds like you do need to have it looked at. I was trying to say that without the fan, there is not much (or any) air circulation that occurs when you sit idle. Most modern cars have air flow from a low fan setting that is on even though you have not turned the fan on via the dial and that's what keeps the car warm when sitting idle at a stop light. Good luck.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
mine does the same thing, but only after I re-winterized it. I think that the coolant to water ratio has to be perfect in these cars. Anything else results in the condition you describe.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Thanks for the feedback !
After Tom's note got me thinking, I checked the coolant level again....although the overflow tank was full, when I popped the rad cap, you could see the rad core ! Added a water/coolant mix and it seems to have fixed the issue !
I thought the fluid in the overflow tank was supposed to be sucked back in to the rad, keeping it topped off, and that you checked the rad fluid by just looking at the level in the tank. Why would the tank be full, and the rad itself low ?
As you probably deduced, I don't know much about cars <g> !
Dean....
BurmaShave wrote:

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
D Larsen ha scritto:

I had the same on my '91 eclipse: the water pump was gone and the head gasket burnt, so I had to fix both: the water pressure was not even in the circuit and the overflow tank was everytime full while the engine was dry. Now everything is ok.
andrea
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Andrea,
That makes sense....if the water pump is shot, I guess you're not going to get any circulation/pressure. Wouldn't your temp gauge creep higher and higher, though, as the coolant decreased ? Mine stays right in the middle rather than rising towards the "high" end....assuming the temp sensor isn't shot, too <g> !
Dean....
Andrea wrote:

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
D Larsen ha scritto:

The temperature sensor is in a good position, so even if you have no liquid at all, when the temperature raises over 90C the vents start and, for this reason, it's difficult to overheat: it only occurs when also the vents are off.
But, since only old VW's are air-cooled, it's better to fix the water pump LOL. In the meanwhile, check water level daily: all in all water is free ;-)
andrea
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Ahhh....makes me long for my old '68 VW Beetle...the "Blue Max".....didn't have to mess around with all this radiator/coolant stuff <g> !
Thanks for the feedback !
Dean....
Andrea wrote:

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
If it does not siphon the coolant back in as the engine cools, then it would seem to point to a leak somewhere or possibly a bad radiator cap. Replace the radiator cap and if you are lucky it may solve your problem permanently. If not, then you should have the cooling system pressure tested to find the leak.
Bob

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Bob,
Thanks for your input on the issue ! "Siphon"....THAT'S the word I was looking for before <g> !
By training, I'm a civil engineer, not a mechanical engineer or an automotive engineer <g>
(Joke :
Q: What's the difference between a mechanical engineer and a civil engineer ? A: Mechanical engineers build bombs; civil engineers build targets <g> )
Anyway....I would think that the siphon would only work if the system was "closed". However, I note that my wife's Eclipse has what looks like an overflow tube coming off the holding tank. To me, that seems like it's open to the outside atmosphere, and the only thing you might "siphon" back in to the system is air, rather than coolant into the cold engine <g>
Your observations make me think further....many times, after driving the car, I smell that distinct odor of hot coolant outside the car...although nothing is obvious on the engine or the ground ! I'll check closer for leaks, and maybe even pop for a new rad cap....thanks for the advice on areas to check !
In the meantime, as Andrea said, water is cheap....
Dean....
Bob Shuman wrote:

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
If the radiator has a pressurized cap, then the radiator and engine are indeed "closed". The fact that the coolant recovery has an overflow is of no consequence since the overflow is at the top and the feed line from the radiator is at the bottom. When the coolant in the closed system cools and contracts, the coolant is drawn from the bottom of the tank back into the radiator. When the coolant heats up and expands, it spills into the coolant recovery tank once the pressure exceeds the design rating on the cap/system.
Bob

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Bob,
If the system was configured as you describe, then I would agree that the system is "closed", with the "weight" of the coolant in the overflow tank acting as a "lock" (providing the pressure of the system didn't exceed that "weight" !). However, both the line from the rad, AND the overflow tube connect on the top of the tank, in an L-shaped connection that's part of the overflow tank cap ! Thus, it seems to me that there's no way the coolant can be drawn back into the rad.....just went out and eyeballed it, and that's the way it's configured....weird, eh <g> ??
Maybe I should try plugging the overflow tube and see what happens.
Dean.....
Bob Shuman wrote:

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
There is a pressurized cap between them. The feed tube goes down into the recovery tank so draws from the "liquid" )bottom) and not the "air" (top) portion of the tank. The overflow tube should be shorter and will direct any overflow to the overflow drain tube.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
If the connection from the radiator cap doesn't have a tube extending to the bottom of the overflow bottle, the the overflow system can't work correctly. If there is a small nipple on the bottom of the cap where the tube from the radiator connects, you can attach a section of rubber hose there so that it reaches to within a fraction of an inch of the bottle's bottom. If there is no nipple, you will need to replace the cap, or drill a hole in it and get a longer hose to connect to the radiator overflow that will reach to the bottom of the bottle.
G. R. Woodring
On 4/2/2007 7:05 PM, D Larsen wrote:

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here. All logos and trade names are the property of their respective owners.