thermostat???
 

hello,

i've got a '99 WJ, the heat coming from the heater isn't so hot anymore, even when it's wide open. is that an indication i need a new thermostat?

thanks.

Re: thermostat???
 

what is your water temp at? does the engine get hot?

Re: thermostat???
 

everything is normal

Re: thermostat???
 

weird... see if it was the thermostat, then the truck would not reach normal operating temperature... it would stay well below it...

have you checked that your air inlets into the cabin to see if they're blocked?

Re: thermostat???
 

You should check the motor that controls the blend air door on the heater box. Sometimes the motor goes, sometimes the actual blend air door breaks (it's just plastic). The motor you can get at from the passenger side behind the glove box. The blend air door itself, it buried in the heater box itself, and requires a fair amount of work to get at. It's a little quicker if you're willing to go at it with a dremel cutting tool. Try this link:

Blend doors fixed with the HeaterTreater*Pics and write-up* - JeepsUnlimited.com Forums

You might also have the heater core flushed.

Re: thermostat???
 

thanks for the help