car runs hot with ac on
07-31-2010, 03:06 PM
#1
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car runs hot with ac on
I cant figure out why but when running down to highway with the air on my cars temp gauge goes to the L on the dash gauge. and when you turn the air off it goes back to the M, why would the ac make the car run hot, the fan works as it should. never tried it in town because of the fear of over heating, granted it has been 95 degress the past 3-4 weeks but still it runs fine untill you turn the air on than it goes to the L within 10 mins of runnins the a/c.
Car has brand new water pump, flushed system, new coolant, 180 thermostate.
Car has brand new water pump, flushed system, new coolant, 180 thermostate.
07-31-2010, 03:39 PM
#3
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ok I may try to flush it again. another thing is it seems to run cold until i hit town which is about a 20 min ride to work everyday it runs on the O on the gauge and when you get into town it finally gets up the the M. where would be a good place to plug a aftermarket gauge into the water jacket to read actual temp
07-31-2010, 03:59 PM
#4
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Flushing it will likely be a wasted effort, once these new aluminum radiators clog they are pretty much clogged for life.
No one bothers to change coolant any more, and after 4 to 5 years the anti-corrosion additives have broken down to nothing--thats when the aluminum builds up that white aluminum-oxide corrosion which insulates and eventually clogs the passages.
No one bothers to change coolant any more, and after 4 to 5 years the anti-corrosion additives have broken down to nothing--thats when the aluminum builds up that white aluminum-oxide corrosion which insulates and eventually clogs the passages.
07-31-2010, 04:08 PM
#5
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Flushing it will likely be a wasted effort, once these new aluminum radiators clog they are pretty much clogged for life.
No one bothers to change coolant any more, and after 4 to 5 years the anti-corrosion additives have broken down to nothing--thats when the aluminum builds up that white aluminum-oxide corrosion which insulates and eventually clogs the passages.
No one bothers to change coolant any more, and after 4 to 5 years the anti-corrosion additives have broken down to nothing--thats when the aluminum builds up that white aluminum-oxide corrosion which insulates and eventually clogs the passages.
its a 3 row
and what about putting in a aftermarket temp gauge?
07-31-2010, 04:19 PM
#6
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I wouldn't, the OEM radiator seems to have done it's job as intended for the best part of 15-years--I'd buy an OEM replacement for $105.
As to an after market temperature gauge, I guess that if you you have money to spend and want a gauge that goes up to 190° or so and then stays there (that's what the thermostat does) then go for it...
As to an after market temperature gauge, I guess that if you you have money to spend and want a gauge that goes up to 190° or so and then stays there (that's what the thermostat does) then go for it...
07-31-2010, 05:02 PM
#7
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I wouldn't, the OEM radiator seems to have done it's job as intended for the best part of 15-years--I'd buy an OEM replacement for $105.
As to an after market temperature gauge, I guess that if you you have money to spend and want a gauge that goes up to 190° or so and then stays there (that's what the thermostat does) then go for it...
As to an after market temperature gauge, I guess that if you you have money to spend and want a gauge that goes up to 190° or so and then stays there (that's what the thermostat does) then go for it...
where would be a good place to tap into to place the afermarket gauge. on my 5.0 I bought a aftermarket thermostate housing that accepted a aftermarket gauge plug.
Last edited by 96meangreengt; 07-31-2010 at 05:06 PM.
07-31-2010, 05:19 PM
#8
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I doubt it would be any more accurate, the OEM gauge is as accurate and repeatable as most small automotive gauges are, it just doesn't have have real numbers as you said. The gauge face could be changed (maybe thats a good idea for an after market product).
The thermostat housing could be easily machined for a small thermocouple, as could the crossover tube.
My point is that I view it as unnecessary on an essentially stock engine. The only thing it will reveal is the temperature rising and then stabilising (which will be around 190°F with a 180° Ft-stat)--in very cold weather it may drop 2°-4°, in very hot weather with the AC on it may rise as much as 5° to 10°.
The stock gauge can indicate this, mine will vary by 1/2 "needle-width" in those situations.
The thermostat housing could be easily machined for a small thermocouple, as could the crossover tube.
My point is that I view it as unnecessary on an essentially stock engine. The only thing it will reveal is the temperature rising and then stabilising (which will be around 190°F with a 180° Ft-stat)--in very cold weather it may drop 2°-4°, in very hot weather with the AC on it may rise as much as 5° to 10°.
The stock gauge can indicate this, mine will vary by 1/2 "needle-width" in those situations.
07-31-2010, 05:25 PM
#9
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I doubt it would be any more accurate, the OEM gauge is as accurate and repeatable as most small automotive gauges are, it just doesn't have have real numbers as you said. The gauge face could be changed (maybe thats a good idea for an after market product).
The thermostat housing could be easily machined for a small thermocouple, as could the crossover tube.
My point is that I view it as unnecessary on an essentially stock engine. The only thing it will reveal is the temperature rising and then stabilising (which will be around 190°F with a 180° Ft-stat)--in very cold weather it may drop 2°-4°, in very hot weather with the AC on it may rise as much as 5° to 10°.
The stock gauge can indicate this, mine will vary by 1/2 "needle-width" in those situations.
The thermostat housing could be easily machined for a small thermocouple, as could the crossover tube.
My point is that I view it as unnecessary on an essentially stock engine. The only thing it will reveal is the temperature rising and then stabilising (which will be around 190°F with a 180° Ft-stat)--in very cold weather it may drop 2°-4°, in very hot weather with the AC on it may rise as much as 5° to 10°.
The stock gauge can indicate this, mine will vary by 1/2 "needle-width" in those situations.
Ok thanks, my big thing is there is no numbers, It would just make me feel better if I new how hot it was when it goes to the L on the temp gauge. basicaly it will jut give me a peace of mind that its not gonna hurt it if it goes that high.
Would you happen to know what the temp would be for the M, A, L on the temp gauge. if I knew that I would put asside the option for an aftermarket gauge. thanks
07-31-2010, 05:47 PM
#10
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It won't go to "L" with the new radiator...
As to the actual temperatures all I know is that straight up is about 210°F, and one "needle width" to the left is 190°F or so. The gauge display is non-linear, meaning that as the coolant temperature moves further outside of the normal range the needle swings faster.
This is a good thing as it will draw your attention to an abnormal situation (as your OEM gauge did) faster than would a conventional linear display--see what I mean about "it ain't broke"...
Here's the sensor output voltage and resistance for various temperatures:
I t would be simple enough to use a resistance substitution box in place of the sensor to calibrate the gauge--maybe I'll add that to my "to do" list...
As to the actual temperatures all I know is that straight up is about 210°F, and one "needle width" to the left is 190°F or so. The gauge display is non-linear, meaning that as the coolant temperature moves further outside of the normal range the needle swings faster.
This is a good thing as it will draw your attention to an abnormal situation (as your OEM gauge did) faster than would a conventional linear display--see what I mean about "it ain't broke"...
Here's the sensor output voltage and resistance for various temperatures:
I t would be simple enough to use a resistance substitution box in place of the sensor to calibrate the gauge--maybe I'll add that to my "to do" list...