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Discussion Starter #1 (Edited)
I've had this problem for some time now (I would say about 2 years), it only happens in summer. The temperatures where I live range between 105 and 118 degrees in summer. The car overheats when is idle with the A/C on after 20 or 25 min approximately. So far I already changed (all new):
  • Radiator
  • Fan,
  • Installed an auxiliary fan
  • Water pump (had a very small leak)
  • Thermostat
  • Upper hose (the lower hose is not bent so as to not to let the water flow )
  • Thermostat housing (had a very small leak)
  • A/C Condenser (it was very dirty, I thought it might be blocking the airflow)
  • I burped it
  • Checked the head gaskets (they are fine)
.....and the problem continues ?... does anyone have any ideas?
 

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Wow, you hit all the high spots. You can confirm the fans run? I know you changed them. Does it quickly come down to correct temp when you drive? Confirmed the upper hose is pushing water to the radiator? I know you've probably done all the steps, but here we just know you have a problem ;)

A Guy
 

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I've had this problem for some time now (I would say about 2 years), it only happens in summer...
Define "overheats"
Does it boil over, peg the gauge, what is the actual temp of coolant?
 

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I agree - what temperature. Give us numbers and timelines. It sounds like with your climate, you would benefit from a 180 deg F stat modification, to get that coolant through the radiator sooner. However that is likely not your main problem.

Have you considered the internal temperature measurement device is off or reporting inaccurately? It's just a thought.

It sounds to me like you may have air still in the system, or a small leak still which is causing a lack of thermal performance. With all of the things you replaced, I find it really odd that you're still having issues.

Did you use MOPAR OAT OEM antifreeze? And not that universal garbage?
 

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Why are you idling that long?
 
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That's also a fair question. 20 minutes is a long time to idle.
 

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Also, how did you "check" head gaskets? A compression and leak down test? Other than that it's actually looking at them but then you have to replace them. Have you pulled the spark plugs to see if any are white?
 

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Define "overheats"
Does it boil over, peg the gauge, what is the actual temp of coolant?
Good questions.

Really the OP needs to provide details of the suspected overheating. What is the actual coolant temperature? An OBD2 code reader/data logger can read this from the engine controller via the OBD2 port. This value is the value the engine controller uses in its fueling calculations and for other things.

Is the coolant fan or fans running? Is there a good amount of air being pulled in? And blown out of the radiator? I would not advise the OP to stick his hand down in the engine compartment to check for this but to at a safe distance try to judge the air flow to see if it is reasonable.

((I had a car with two cooling fans. While one was pulling in a good amount of air and at the exhaust side of the radiator -- just ahead of the front tire wheel well -- the engine was mounted in the back of the car behind the rear axle -- a good blast of (hot) air was coming out the other radiator fan while obviously running was not moving nearly as much air. Tech checked and found no fan stage errors but noted the sub par performing fan was drawing way more current than the what the good fan was drawing. I had him replace the fan motor drawing the higher amount of current and afterwards both radiator fans behaved identically. Might add even in this case and once before when one fan motor shaft snapped and the car only had one fan operating the engine never oveheated even in nearly 100F heat in Fresno. The A/C system performance was not even affected. What clued me in there was a problem was the fan noise was not quite as loud as I remembered and this prompted me to get out and check fan operation and that is when I found one fan not moving any air even though I could hear the fan motor running.)
 

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Discussion Starter #10
Wow, you hit all the high spots. You can confirm the fans run? I know you changed them. Does it quickly come down to correct temp when you drive? Confirmed the upper hose is pushing water to the radiator? I know you've probably done all the steps, but here we just know you have a problem ;)

A Guy
I corrects the temp a little while after I hit the road. The fans are running, as a matter of fact, when i turn off the car, the auxiliary fan remains on for a few more seconds. The auxiliary fan turns on with the high speed of the regular fan kicks in. The upper hose is not bend or anything that wold prevent the water to flow. ?
 

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Discussion Starter #11
Define "overheats"
Does it boil over, peg the gauge, what is the actual temp of coolant?
I usually put the digital thermometer on the dash to monitor the temp. the gauge starts to pass the middle mark at 235 degrees, I've had moments that the temperature reaches the 245 degrees; at this point the gauge is almost to the top
 

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Discussion Starter #12
I agree - what temperature. Give us numbers and timelines. It sounds like with your climate, you would benefit from a 180 deg F stat modification, to get that coolant through the radiator sooner. However that is likely not your main problem.

Have you considered the internal temperature measurement device is off or reporting inaccurately? It's just a thought.

It sounds to me like you may have air still in the system, or a small leak still which is causing a lack of thermal performance. With all of the things you replaced, I find it really odd that you're still having issues.

Did you use MOPAR OAT OEM antifreeze? And not that universal garbage?
The stat that I have is 202 degrees, that's the temp it opens, which means that after the 202 the stat is always open, and unfortunately that doesn't prevent the temperature to rise up. After all I've done, it crossed my mind the temp sensor too, but no, I haven't checked it yet. It might be a good idea.

I would discard a leak since the water reservoir keeps the levels normal.
 

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Discussion Starter #14
The stat that I have is 202 degrees, that's the temp it opens, which means that after the 202 the stat is always open, and unfortunately that doesn't prevent the temperature to rise up. After all I've done, it crossed my mind the temp sensor too, but no, I haven't checked it yet. It might be a good idea.

I would discard a leak since the water reservoir keeps the levels normal.
Also, the antifreeze that I use is the one from Autozone, is not the OEM ? Could that be the issue?
 

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Discussion Starter #15
Also, how did you "check" head gaskets? A compression and leak down test? Other than that it's actually looking at them but then you have to replace them. Have you pulled the spark plugs to see if any are white?
I borrowed the block tester from Autozone.
 

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I idle a lot too, the car should not overheat.

Also, the antifreeze that I use is the one from Autozone, is not the OEM Could that be the issue?
This might be some of your troubles. You should always use the correct factory coolant to ensure there are no compatibility issues that would cause a gunked up radiator and cooling system. Mixing coolants can cause a real mess.

Sent from my SM-N960U using Tapatalk
 

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Also, the antifreeze that I use is the one from Autozone, is not the OEM ? Could that be the issue?
You should be using MOPAR antifreeze or something like Zerex GO-5. Are you mixing 50/50 with distilled water? Anything other than 50/50 can affect your boiling point and freezing temps.
 

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Discussion Starter #18
Good questions.

Really the OP needs to provide details of the suspected overheating. What is the actual coolant temperature? An OBD2 code reader/data logger can read this from the engine controller via the OBD2 port. This value is the value the engine controller uses in its fueling calculations and for other things.

Is the coolant fan or fans running? Is there a good amount of air being pulled in? And blown out of the radiator? I would not advise the OP to stick his hand down in the engine compartment to check for this but to at a safe distance try to judge the air flow to see if it is reasonable.

((I had a car with two cooling fans. While one was pulling in a good amount of air and at the exhaust side of the radiator -- just ahead of the front tire wheel well -- the engine was mounted in the back of the car behind the rear axle -- a good blast of (hot) air was coming out the other radiator fan while obviously running was not moving nearly as much air. Tech checked and found no fan stage errors but noted the sub par performing fan was drawing way more current than the what the good fan was drawing. I had him replace the fan motor drawing the higher amount of current and afterwards both radiator fans behaved identically. Might add even in this case and once before when one fan motor shaft snapped and the car only had one fan operating the engine never oveheated even in nearly 100F heat in Fresno. The A/C system performance was not even affected. What clued me in there was a problem was the fan noise was not quite as loud as I remembered and this prompted me to get out and check fan operation and that is when I found one fan not moving any air even though I could hear the fan motor running.)
A little bit over a month I took the car to the shop, they told me that the fan was not blowing enough air, it was weak according to them, so I bought the OEM mopar fan (almost 300 bucks, I got it from Rockauto), now it takes a little bit longer to overheat, but definitely it didn't solve the issue. ?
 

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Discussion Starter #19
I idle a lot too, the car should not overheat.

This might be some of your troubles. You should always use the correct factory coolant to ensure there are no compatibility issues that would cause a gunked up radiator and cooling system. Mixing coolants can cause a real mess.

Sent from my SM-N960U using Tapatalk
You should be using MOPAR antifreeze or something like Zerex GO-5. Are you mixing 50/50 with distilled water? Anything other than 50/50 can affect your boiling point and freezing temps.
I didn't mix them , when I put the one from Autozone I drained completely the system. I used the Preston 50/50
 

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What are your actual coolant temperatures based on the car HUD gauge? I don't know what you're talking about in regards to the digital thermometer to measure the temperature? What?

You really should use OEM antifreeze. The universal replacements are not nearly as good - you can find test reports and comparisons online.
 
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