Heater and operating temps issue
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Heater and operating temps issue
Hey guys, so I've just noticed the other day when I was driving to to work in the morning about 50 something degrees out that my colant temps took a bit to get to 190 but then when it did I kinda just stayed there and even went down a little. I've never seen it take so long to get up in temps even in the cold. So today when I drove home I noticed the same thing and even tries the heater. No real hot air or not even at some points. When I stopped to ideal after my drive home the temps started to kinda creep up and a little hot air started to blow. I'm thinking maybe the thermostat. Gonna check for codes tonight but any help would be very grateful. Thanks in advance
Melting Slicks
Joined: Nov 2017
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Thermostat not opening would possibly explain your no heat issue, but if it wasn't opening, your coolant temps would keep going up instead of staying around 190 (which is around it's temp rating, so sounds normal). Swapping the tstat is a cheap and easy attempt, might as well try it first and go from there.
Melting Slicks
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Absolutely. But if it's open, you'd be getting heat in the car.
Stuck open = slower to get to operating temp, but would have heat in the car.
Stuck closed = no heat in the car, would be prone to overheating
It's definitely possible that it's stuck partially open, but I'd expect SOME heat in the car (in theory anyway).
Definitely worth replacing to find out!
Stuck open = slower to get to operating temp, but would have heat in the car.
Stuck closed = no heat in the car, would be prone to overheating
It's definitely possible that it's stuck partially open, but I'd expect SOME heat in the car (in theory anyway).
Definitely worth replacing to find out!
Pro
Joined: Dec 2014
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From: Cincinnati Ohio
What you describe sounds like a thermostat that is stuck open or leaking. When the engine is cold, the thermostat prevents coolant from circulating through the radiator which directs the warming coolant to the heater core. This is why we have warm air coming through the vents even though the engine has not reached operating temperature. Once the coolant reaches the set point of the thermostat, it begins to open which directs some of the coolant through the radiator.
Melting Slicks
Joined: Nov 2017
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Do some Googling or parts look up on a parts site to confirm, but I believe 97-03 are different than 04. There was a change in there somewhere, I just don't know for sure what year(s). On my 01, it's a simple pull and swap with negligible loss in coolant. Just need to make sure you have the new part in one hand, with o-ring in place, ready to put on as soon as you pull the old one.
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Well I did the thermostat and topped off the fluid and did a couple heat cycles with the heater on and burped the system buy letting the air out from the cap. At idle temps seemed good the heater was even getting hot when it reached in the 200s. I even went on a spirited drive and everything seemed fine. But then this morning the same thing happened. Only got to 196 and not hot air when I was driving to work today. What do I need to do. Thanks
Pro
Joined: Dec 2014
Posts: 681
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From: Cincinnati Ohio
The first question is - does your engine come up to temperature more quickly with your new thermostat? You previously wrote that the engine was slow to come up to temperature. So has that changed? When regular city or highway driving, do you get up to temperature within a few miles and hold in the 190 degree range? If so, that suggests your thermostat is working correctly.
Next thing to check are your heater in and out pipes/hoses. With the engine at temperature they should be hot. If they are, you probably do not have a blockage. If the inlet is hot and the outlet is cool, you may have a blocked heater core or pinched outlet hose.
If the in and out line are hot, you may have a temperature blend door problem, Do you have automatic temperature control or manual?
Next thing to check are your heater in and out pipes/hoses. With the engine at temperature they should be hot. If they are, you probably do not have a blockage. If the inlet is hot and the outlet is cool, you may have a blocked heater core or pinched outlet hose.
If the in and out line are hot, you may have a temperature blend door problem, Do you have automatic temperature control or manual?
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Thanks for thr response... in the morning it seemed to get warmer a little quicker than before. It is definitely running warmer at around 196 as before it would be at 184. When I got to work and sat in the parking lot it was going to 210. I have the dual climate control not the manual one. I'll check the hoses when I finish work to see if they are hot.
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Update : just realized on my way home tonight that the passenger side was blowing heat but not the driverside and temps looked good. It was 196 at 58 degrees outside ... would that be the actuator or is that still a heater core thing
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I didnt have any codes as of the other day but ill check tomorrow... I've also read that I need to pull number 27 fuse for 60 sec or something like that. Also I am confused with this actuator issue. Would it have any corelation with my low operating temps from before I changed the thermostat or is that just a coincidence.
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