Maximum heater temperature too low

CNYGERMANY

MEMBER
1996 CHRYSLER NEW YORKER
3.5L
6 CYL
2WD
AUTOMATIC
95,000 MILES

Hello,

my HVAC is working fine so far but the maximum heater temperature is too low. Depending on the outdoor temperature the heater gives not more than approximately 15° Celsius. Temperature control works fine from hot to cold and reverse, A/C works too.

Ran the auto diagnostic procedure as explained here by KHLOW2008. Error code is 34 - Engine Temperature Message Not Received.

How to proceed?

Thanks!

3 Replies

ASEMASTER6371

MECHANIC
52,797 POSTS

Good morning,

This sounds like it could be a thermostat stuck open not allowing the engine to heat up to the proper temperature. That will give you reduced heat from the system.

The other possibility is the heater core. It may be clogged with debris. You would need to remove both hoses from the firewall and use a garden hose to flush the core back and forth. Then hook the hoses back up and fill the coolant and retest.

https://www.2carpros.com/articles/car-heater-not-working

The intake manifold needs to be removed to access the thermostat. I attached the procedure for you below.

https://www.2carpros.com/articles/replace-intake-manifold-gasket

Roy

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