Chrysler Repair: 99 cirrus 2.5 v6: low heater output, head gasket, electronic meter


Question
QUESTION: the heater stopped workimh
it acts like thermostat is stuck open
water circlates to soon
changed it still did it so i went to dealer   they said it took special one for that motor   57.00   didnt work
electronic meter shows water in motor is running aroun 150 - 160
but taking cap off couple minutes after starting motor
and it is cirrculaating
it never overheats   but if u turn on defrost u lose the luke warm air
if it isnt to cold out and u leave heater fan on low it will heat inside very little
i have put over 1000 miles on it like this   just cold
one more thing   it was getting up to 29 miles per gallon before this  now i lost that also
can u help   thank you   the 2 dealers have no clue

ANSWER: Hi Bob,
If the system is indeed running at 150-160 then there is an issue with the thermostat opening too soom. When you installed the new thermostat was the sprin facing inward as it should be?
If not remove it and reverse the position.
Are the heater hoses about equally hot? They should be. But if the system is not at 195 you won't get much heat.
What does the engine temp gauge show the coolant temp to be after you have driven it far enough to anticipate it will be at operating temperature?
Roland
PS Sorry for the delay but I just found your question in the "pool" to which it had been referred by Kevin. If you would be so kind as to 'rate' my answer I would be appreciative.
See below.

---------- FOLLOW-UP ----------

QUESTION: its not the heater core
 it is in engine     for some reason some how the water is bypassing the thermostat
yes the spring of it is toward head  the gauge is running about one fourth    and it use to run halfway
i know enough to know that it is acting like thermostat is stuck open  but it isn't
is there any way the water could be passing through a bad head gasket letting it circulate without it overheating
thats what it seems like

ANSWER: What is the labelled opening temp of the thermostat that you bought? It may be lower than the old one. You would want a 195 but sometimes they stock 180 instead.
You could try back-flushing the heater core by removing the two hoses and forcing water from an outlet through it. It may be that the core is partially blocked. Otherwise I don't see anyway for a by-pass around the engine that would not also involve a frank leak.


---------- FOLLOW-UP ----------

QUESTION: it is not thermostat  it is not in backwards   it is 195
it isnt bad   i put 3 in it in one week
so all three are not bad   when i take them out they r shut
the heater cor eisnt blocked because the motor isnt heating up    if u turn defrost on the air inside is getting even colder b cause core acts as a radiator also
but i am telling u ithe water starts moving within a couple of minutes of starting even when it is cold like its been
i take coolant cap off by the thermostat and it water is moving fast
but it dont over heat and i lose no water   but no heat even in motor   i test temp with electirc temp gun

Answer
Is it possible that your radiator fan is running all the time (faulty relay or faulty temperature sensor could cause that)?
Look at the housing where you mount the thermostat to make sure that it isn't cracked is all that I can suggest to you.
The air in the cabin will get colder yet if you use the defrost because that also turns on the A/C compressor. I know of no other expanation, Bob. But again, try back-flushing the heater core as that may be clogged up. The hoses should both be warm about at the same temp, otherwise you have poor flow through the heater core. Another possibility is that the mode door in the HVAC box is not sending the air over the heater core so that would explain why no warm air in the cabin.