Does your engine temp show a bit low, or right at 210 (Also is yours an auto or manual)? Just curious if what I ran into is common. I’ve seen 1 or 2 other members report it.
No heat
- Thread starter Morks
- Start date
Does your engine temp show a bit low, or right at 210 (Also is yours an auto or manual)? Just curious if what I ran into is common. I’ve seen 1 or 2 other members report it.
OP said he just had the heater core changed ! 1st thing to check is your top, is it on ? 2nd thing to check is are your windows rolled up, if its cold outside and your windows are down the heater wont be very efficient ? next thing is your radiator closer to the front or rear bumper, if your radiator is in the back that hot water will have a long trip to get to the core so i'd have it moved closer to the front ? IT'S YOUR FUCKING HEATER CORE
a known problem with aftermarket cores !
If that's true would the heater lines be hot going to and from to the touch and the same temp on a thermal gun?OP said he just had the heater core changed ! 1st thing to check is your top, is it on ? 2nd thing to check is are your windows rolled up, if its cold outside and your windows are down the heater wont be very efficient ? next thing is your radiator closer to the front or rear bumper, if your radiator is in the back that hot water will have a long trip to get to the core so i'd have it moved closer to the front ? IT'S YOUR FUCKING HEATER CORE
that part has me stumped, but you said you know the blend door is working. so the only other thing in the system is the core and it was just changed. i'd take it back to whoever changed it. i will check mine with a IR gun tomorrow and see if their the same or close !
I took it to a "reputable shop" and it really is, never heard one bad thing and there aren't many in my area. After getting it done I just made sure it did not leak. Not thinking about checking the heat as I bought it in the middle of the summer and being my first vehicle I had not a clue what I was in for lol. But about 4-5 weeks later I thought to check it and they said "it's most likely a clogged line and said they'd have to diagnose and charge again to see issues". (that's where the tool addiction came into play lol)
I will probably try giving them a call again just to see if they say anything different but I am talking just over a year ago, not afraid to take the dash apart just want to make sure that's what it is before I do it. And okay, if I remember correctly I got around 140 degrees celsius or just under of heat out of both lines
If you can move it freely, and it isn't changing the temperature of the air coming out of the vents with the jeep running, I'd suspect the door is no longer attached to the part you are moving. If you can you rotate it more than 180 degrees, that would pretty much prove it isn't properly attached. This video shows how much it should be able to turn (No Heat Jeep Trouble Shooting)
If the heater core lines are close to the same temperature going in and out, then it isn't blocked and is working like it should. When the heat is working properly with air also passing through the heater core, the return line will be slightly cooler than the line going in, but still hot to the touch.
Turns exactly how it should, maybe freely wasn't the best word choice, moves smoothly, and when it gets to either hottest or coldest I can hear the flapper hitting the plastic in the air box closing it fully off to either cold or hot. (I feel a difference in temp just goes from cold to less cold kind of thing but get warm air slightly on speed 2 like previously mentioned.)
it sux that your going to have to go back into it after having paid to have it fixed. but i'm afraid it really is your only fix. if it was a good shop they would atleast take a look at it for you if you had it done this summer !
Another possibility is that the air path through the heater core is blocked. Maybe leaves or some other sort of debris. That would prevent air from going through it and warming up. That seems unlikely if a new core was installed this past summer.
yeah not crazy worried if I have to take apart the dash I'll just wait for the summer but hopefully just have a different daily before then so I can beat the crap out of this one for real lol!
AG10
Member
well the batteries were all crusted up on my IR thermometer and it's FUBAR ! but put a stick thermometer in my dash vents and it is 125-130deg coming out with fan on high. but i cant figure why you get heat when you 1st switch it then turns cold again unless your actuator is loosing its vacuum and allowing the door to go back to its neutral position ,that might be the direction to go. i know your 2004 is different than my 97. but if you have or can get a hand vacuum pump (avail. at parts store) and put a vacuum to your control actuator and see if it holds it open or lets it go back to open.
The actuator for the blend door is not vacuum operated. It is a slide cable on older models, and on the 2004 it is a an electric actuator. (The doors that control which vents the air goes into and out of the system are vacuum operated.)
135 degrees at the heater hoses when the jeep has been fully warmed up, is way to cold. Those hoses should be at 180-190 degrees with an infrared thermometer.
see above
If you put your mode door setting on vent, fan speed @1, then put a thermometer in the center vent. record your reading.
Now increase the fan speed to high, is the temperatrue reading now less then when you had it on speed 1?
If so you may have a blockage somewhere that is restricting flow into the heater core. Possibly the new core.
If you have access to a scan tool that reads live data, see what your coolant temp sensor is reading after warm up.
Not neccesarily true. If you have a restriction or reduced coolant flow into the heater core, changing the fan speed from low to high will cause the core temp to drop dramatically, therefore causing a sharp decrease in output temperature at the vents.
Swamp Yankee
TJ Enthusiast
When I get around to replacing my new POS aftermarket heater core that does not put out heat and the inlet and outlet are both hot, I will disassemble it and tell you why it’s a piece of shit. There is a possibility of crappy turbulators as reported in other posts, or there is not enough sealer which allows the coolant to bypass and not even go through the cores tubes where the air passes by to heat it up.