I have acquired a 2004 Dodge Stratus to replace my 2007 pontiac G6 when the lease is up. It’s got a 2.7 V6 in the stratus, and a 3.5 V6 in the G6.
After about 12 minutes in the G6 (ie 12 minutes since starting on a 30 degree day) with the heat running on full, it’s intolerable in the car.
After a full 25 minutes in the Stratus, the temp in the car with the heat on full (in both cases coming out of the floor vents) it’s just starting to get too warm to be comfortable.
I have checked the coolant level and it’s full. The temp gauge goes to the low side of the middle, for all that is worth.
I notice that the temp of the air coming out of the vents on the G6 is hot enough to be slightly painful if you put your hand an inch from the vents (let’s call it the kind of pain you feel for an instant getting into a hot shower…not first degree burn painful, but on the edge of “that’s too hot”). On the Stratus, it never really approaches this point, I could keep my hands by the vent for minutes and not really experience any pain at all, though it is very warm.
Is this variance between makes typical? I have a short drive to work, about 15 minutes, and I would like to be warm for at least a fraction of the drive. Doesn’t look like that’s going to be possible in the Stratus, unless someone on here has some other ideas for me to check.
What temp should the air coming from the vents be?
it all depends on the car. My Volvo comes from the land of the ice and snow, From the midnight sun where the hot springs blow. as a result I can put the inside of the car to over 120F in a few miles. (I did it once just to try)
On the other hand, other cars don’t have as good a heater.
there could also be a problem with the heater core, or an air pocket in the heater core that is preventing a good circulation of coolant.
Some cars require burping of the heater core, or a vacuum be sucked on the sytem before filling to ensure no air pockets.
If the thermostat was stuck open, it wouldn’t get heat at all, would it? In Michigan temps, with coolant constantly circulating through the radiator, I would think it woudl never get warmed up.
Also, the Stratus is built int he land of ice and snow, too…they’re assembled in Sterling Heights, Michigan
A faulty thermostat is one possibility – lukewarm heat, as opposed to hot heat, is one symptom of a weak thermostat. If the thermostat is okay, I would next check all the heat-related controls to see if some device is failing to achieve its full-heat position, and next check for restricted flow through the heater core. If everything checks out, it may just be a marginal heater design, but most cars will give hotter heat than you describe for the Stratus.
Even with the thermostat completely stuck open, usually the car will eventually warm up to the point that there’s heat, but usually it won’t get all the way up to standard operating temperature.
Incidentally, a few years go I bought a very used car (a '74 Corolla) which would take a long time to warm up, but eventually would put out enough heat to keep the car cozy in Montana winter temperatures. When I went to change the thermostat, it was gone-- there was nothing in the housing! After I put one in, the heat was awesome.
One thing you could do to narrow it down is if you’ve got one of those cooking thermometers with the big long metal probes, try sticking it in the vent next time you make your commute. That should help you narrow down whether the problem is that the air coming out of the vents isn’t hot enough (pointing to a t-stat or some other mechanical issue) or if there simply isn’t enough of it coming out (which might point to just a crummy heater).
No, the air temp from the vents won’t be hot enough (should be ~150’ F w/ blower on high) whether the problem is a bad thermostat, restricted flow through the heater core, a faulty blend door, a faulty heater control valve, or what-have-you. High enough temperature but not enough of it coming out happens when the blower speed is low.
Is there a way to check for restricted flow through the heater core without removing it? Removing the heater core on this car looks to be quite a pain in the rear.
Replacing the thermostat should be easy enough, and thermostats aren’t terribly expensive, so I can go that route first. As long as I am draining the coolant, I might as well flush it out in case that’s the problem, as well, and kill 2 birds with one stone. I don’t think this model uses the 100,000 mile coolant, so I guess it’s possible that it’s due for a good flushing anyhow, at 75,000 miles.
Measure the temperatures at the heater inlet and outlet pipes under the hood. There should be a noticeable difference, around 30-40’F IIRC. First, though, measure the engine temp on the upstream side of the stat housing. It should range from 190-220. If it’s low, the stat is bad. These measurements are fairly easy with an infrared gun type thermometer or certain specialized contact thermometers; they’re difficult to impossible without them.
Or when the car isn’t designed with a vent system or blower that puts out enough air to heat the cabin. I seriously doubt this is the case with any car sold in this country in this day and age, but this was part of the OP’s original question and plus we seemed to be entertaining the notion further up thread. Checking the vent temperature is an easy way to rule this out.
At 30 degrees I don’t even turn the heater blower on.
Seriously the heater blower can be loosing power. I just changed the blower in my pickup Saturday and was amazed at the force the new blower motor had over the old.
I am right now suffering from the inhalation of the black dust I suspect from the brushes on the old motor as I was removing the blower wheel. I had to leave the garage after I whacked the old motor shaft. Just like an instant upper respiratory infection!
It means there’s an air pocket in the system that stymies flow. It can happen from an improper filling procedure or from a leak that allows air to be sucked in. Water pumps work well to move liquids, but are not designed to move gasses. With the system not fully containing liquid, but rather having some liquid and a fair amount of air, there are places where the air can pool up (the heater core is one of them) and stay there. Some air pockets can result in the engine overheating, some can result in no heat from the heater.
ETA: It’s a variation of insufficient (or no) coolant flow through the heater core.
