My max's interior doesn't heat up as warm/fast as before and takes longer than usual to heat. What might be the cause for the "weak heat" syndrome?

 

Stuck Thermostat possibly. For the price of a thermostat and New Coolant, its worth to do first to rule it out.

-matt

 

 

Could also just be really low coolant level. Have you checked it lately?

 

If your car take a long time to warm up, your thermo could be stuck open and so when you think the car is heated up and turn the heat on, its not and pumps out weak heat.

Or you may have air in your coolant lines. A Drain and refil should cure that.

Heater core could be going out. Part I believe isnt too expensive, you have to take out the console to get to it.

 

simple solution.. if ur lazy enough... cover some of the radiator with cardboard.. till you have time to fix it...

 

I have seen that be the issue many times.

 

How bout this one. My car only blows hot air when the revs are above 2200 rpm's. Really fun in the sub zero temps around here lately in stop and go traffic. Could this also be the coolant level?----Thanks

 

Is your car fully warmed up when the heat is on?

 

my guess is it is a stcuk thermostat....it is real inexspencive and easy to replaceso try that first. i just did mine and it is alot better....make sure you do nt use a paper gasket that comes with thermostats alot of the time, go nissan and buy the rubber thermostat gasket which run like $2.50.

 

thanks guys. i'll give the 'ol t-stat replacement a try. found one on jerry rome for just under $10

 

You have air in your cooling system. Have you had a refill or had the coolant drained recently? When the rad was refilled, the colling system wasn't purged of air.
Take the rad cap off, turn the heater on (all the way)-fan on, let the car run. Try to get your revs to about 2000 or 2200 as it does in your car. Top off as needed.

 

Let me restate so I understand correctly. You guys are saying that replacing the thermostat will cause the heat to come on more quickly, if it takes a long time now? I'm just asking b/c I specifically asked the Nissan Dealer to replace the thermostat when he did my water pump 6 weeks ago, and he said if it ain't broke don't fix it. Well if I'm hearing that it might not be working correctly and that's why my heat takes a long time, then that sucks!

 

You will know if your thermostat is bad.

If its bad it will be stuck open or closed. If its stucked closed, your car will over heat pretty fast. If its stuck open your car will take a very noticable lengthy period of time to warm up. If you drive for about 10-15 mins and your car isnt fully warmed up, I'd say the thermo maybe stuck open.

If your car isnt doing that, Its either Air in the coolant lines, or a dying heater core. I'd do a flush as its cheaper and easier than replacing the heater core.

 

I have the same problem. My water temp during the winter barely moves, or if it does, it moves like a centimeter. But during the summer time my water temp is normal. What can be the problem?

 

Thermo is stuck open. My car threw a code for the thermo when it was stuck open.

 

That's interesting. Mine didn't.

 

well mine takes a good 5 - 10 minutes to turn on, if i hit the automatic button, i get nothing at all, no fan or anything for the first few minutes, then as the car warms up, the heats gets better

 

By "only blows hot air" do you mean, "it's cold < 2200" or "it's warm < 2200". My car doesn't blow "hot" air (where I can feel a slight, uh, "sting" on my hand) unless it's idling for a while or "working" ( > 2000). Otherwise, it's only warm - it warms the cabin but not as quickly as the Vulcan (Taurus) in my wife's car.

When I rev the motor, I feel the corresponding heat increase a few seconds later. Like blip the throttle, then 5 seconds later the heat becomes "hot". The car "heats up" quickly and the gauge is pinned at slightly less than 1/2.

It's been like this for > 1 year.