Recent Topics
Trying to fix chainsaw
by turtlevette
06/23/18 06:48 PM
tire rotation
by marine65
06/23/18 06:48 PM
Reese hitch $30 Walmart YMMV
by pda1122
06/23/18 06:14 PM
Managing Anger During Unexpected Tire Change
by TheLawnRanger
06/23/18 06:14 PM
2016 Honda Pilot appears to be consuming oil
by pilot1226
06/23/18 06:00 PM
New belt squeal cause damage to belt?
by pda1122
06/23/18 05:33 PM
Food Safety - If You Have Children
by Zee09
06/23/18 05:15 PM
Reduce TORQUE to COMPENSATE for lubed threads?
by SumpChump
06/23/18 05:02 PM
Chain cleaning and lube
by dadinfo
06/23/18 04:57 PM
Mobil Delvac 1 ESP 5w40 $23.65 at Walmart
by 71Chevyguy
06/23/18 04:36 PM
diesel oil in older engines- RE: cats etc
by 928
06/23/18 04:35 PM
2011 F-150 Ecoboost timing chain replacement
by 14Accent
06/23/18 04:31 PM
My stash of Kendall GT1 almost gone..
by Vern_in_IL
06/23/18 04:30 PM
mobil 1 rebate check
by Fitter30
06/23/18 03:52 PM
Cab mount failure
by ram_man
06/23/18 03:31 PM
02 Saab aero oil?
by Newuser
06/23/18 03:00 PM
Extend wifi range
by clarkflower
06/23/18 02:05 PM
Under valve cover pics 207,000 miles
by WobblyElvis
06/23/18 01:57 PM
Lease Buyout by Dealer
by Throt
06/23/18 01:52 PM
13 Ford Escape
by RedOak
06/23/18 01:10 PM
Newest Members
bwechols, bowupid, pod423, lemaitrix, azzid0906
65303 Registered Users
Who's Online
80 registered (2015_PSD, 2004tdigls, Balrog006, asiancivicmaniac, AndyB, 10 invisible), 1459 Guests and 49 Spiders online.
Key: Admin, Global Mod, Mod
Forum Stats
65303 Members
67 Forums
285870 Topics
4770670 Posts

Max Online: 3590 @ 01/24/17 08:07 PM
Donate to BITOG
Page 1 of 5 1 2 3 4 5 >
Topic Options
#4503649 - 08/31/17 06:06 PM Running Hotter with A/C
Nick1994 Online   content


Registered: 02/19/13
Posts: 10123
Loc: Phoenix, AZ
I've done more testing in this now with my Jeep. I toughed it out and drove in traffic (110 degrees out) and WITH A/C it ran at around 220-222. Once I turn OFF the A/C it goes down to 210-212 within a couple minutes. I did this multiple times driving to work today and then with the A/C on I was stopped at a light on the freeway off ramp and it jumped closer to 230. Turning on the heat and a/c off it went down to 210 after a minute or two.

All cooling components have been replaced.

What causes this? A/C blows pretty cold, compressor makes a little bit of noise but not bad. Compressor doesn't seem like it's extremely hot either. Condenser is clean.

Thanks
_________________________
2015 Hyundai Sonata 2.4L 79k PU 5w30 & OEM
2000 Toyota Camry 2.2L 228k M1 AFE 0w30 & Wix
1996 Jeep Cherokee 4.0L 146k M1 HM 10w40 & Fram Ultra

Top
#4503664 - 08/31/17 06:16 PM Re: Running Hotter with A/C [Re: Nick1994]
danez_yoda Offline


Registered: 07/18/09
Posts: 465
Loc: texas
Did it start doing that or has it done it all along?

If its always done it it could be the temperature sensors proximity to the AC compressor. Compressor gets hot and warms up the temp sensor.

On a 1996 the fluid temp should be controlled with a mechanical thermostat so the engine temperature should not be load dependent.

Also check the electric fan speed through the radiator when the AC is on vs off. It could be that it is slowing down under the electrical load of the AC.

Top
#4503669 - 08/31/17 06:19 PM Re: Running Hotter with A/C [Re: Nick1994]
Reddy45 Offline


Registered: 08/15/08
Posts: 2973
Loc: USA
Maybe I'm not understanding this fully, but that seems quite reasonable. The AC is moving heat that is inside the cab, to the outside -- at the condenser. All of that heat ends up near the engine (which is also under additional load from the compressor), so a small rise in temps seems OK.

Top
#4503676 - 08/31/17 06:22 PM Re: Running Hotter with A/C [Re: Nick1994]
KrisZ Offline


Registered: 12/23/06
Posts: 7473
Loc: Toronto, Canada
The condenser is in front of the radiator, so when you turn on the AC, the hot air coming off of the condenser goes through the radiator next. In effect it reduces the heat removal capacity from the radiator a little bit, hence the increase in the temperature.
_________________________
2015 Dodge Grand Caravan-21k miles.
2006 Mazda 3-155k miles

Top
#4503685 - 08/31/17 06:33 PM Re: Running Hotter with A/C [Re: danez_yoda]
Nick1994 Online   content


Registered: 02/19/13
Posts: 10123
Loc: Phoenix, AZ
Originally Posted By: danez_yoda
Did it start doing that or has it done it all along?

If its always done it it could be the temperature sensors proximity to the AC compressor. Compressor gets hot and warms up the temp sensor.

On a 1996 the fluid temp should be controlled with a mechanical thermostat so the engine temperature should not be load dependent.

Also check the electric fan speed through the radiator when the AC is on vs off. It could be that it is slowing down under the electrical load of the AC.
It's been doing it for a while.

It has 2 temperature sensors. 1 at the front of the engine, not too close to the compressor in the thermostat housing. This gives the reading to the computer.

It has another at the back of the head which gives the temperature to my mechanical gauge on the dash, this is a real gauge not the cluster gauge.

I've replaced the sensors and verified with a scan tool and IR temp thermometer that the temperatures are correct.
_________________________
2015 Hyundai Sonata 2.4L 79k PU 5w30 & OEM
2000 Toyota Camry 2.2L 228k M1 AFE 0w30 & Wix
1996 Jeep Cherokee 4.0L 146k M1 HM 10w40 & Fram Ultra

Top
#4503686 - 08/31/17 06:35 PM Re: Running Hotter with A/C [Re: Nick1994]
Merkava_4 Offline


Registered: 01/30/07
Posts: 17501
Loc: Clovis, CA
It's that clutch fan that's doing it. With electric fans, they run all the time with the A/C is on.

Top
#4503704 - 08/31/17 06:47 PM Re: Running Hotter with A/C [Re: Merkava_4]
Nick1994 Online   content


Registered: 02/19/13
Posts: 10123
Loc: Phoenix, AZ
Originally Posted By: Merkava_4
It's that clutch fan that's doing it. With electric fans, they run all the time with the A/C is on.
It also has an electric fan
_________________________
2015 Hyundai Sonata 2.4L 79k PU 5w30 & OEM
2000 Toyota Camry 2.2L 228k M1 AFE 0w30 & Wix
1996 Jeep Cherokee 4.0L 146k M1 HM 10w40 & Fram Ultra

Top
#4503712 - 08/31/17 06:56 PM Re: Running Hotter with A/C [Re: KrisZ]
gathermewool Offline


Registered: 01/09/09
Posts: 6001
Originally Posted By: KrisZ
The condenser is in front of the radiator, so when you turn on the AC, the hot air coming off of the condenser goes through the radiator next. In effect it reduces the heat removal capacity from the radiator a little bit, hence the increase in the temperature.


+1

The oil in the Forester XT is coolant-cooled. The multi-function display on our Forester XT shows oil temperature. The oil temperature, like the coolant, rises when the A/C is on, even while at highway speeds.

Top
#4503715 - 08/31/17 06:59 PM Re: Running Hotter with A/C [Re: Nick1994]
AZjeff Offline


Registered: 01/14/11
Posts: 2646
Loc: PV Az
So in 110 ambient you see temps bump up 10 degrees with the AC on.

What is your thermostat? Any chance to drop it 10 degrees and give yourself a little room?

This could be a case where a bottle of Redline Waterwetter could do some good.

The Jeep is 21 years old, cut it some slack and roll the windows down! You're a native, 110 is just getting warm. wink
_________________________
86 Samurai 1.3 leftovers
14 RAV4 2.5 5W-20 PP *gasp*
16 Silverado 1500 4.3 Ecotec3, DI, AFM 5W-30 PP

Why know when you can guess?!


Top
#4503731 - 08/31/17 07:15 PM Re: Running Hotter with A/C [Re: Nick1994]
WyrTwister Offline


Registered: 01/13/13
Posts: 1531
Loc: Texas
Is the gauge showing HOT ?

Have it boiled out any coolant ?

Here is my take on this . As long as the coolant is at least 50% - 50% and is circulating properly , you will not damage the engine if it has not boiled off any coolant .

Am I right ? Wrong ?

Best of luck , :-)
_________________________
Wyr
God bless

Top
#4503740 - 08/31/17 07:19 PM Re: Running Hotter with A/C [Re: KrisZ]
Kuato Offline


Registered: 10/23/05
Posts: 7094
Loc: Colorado
Originally Posted By: Reddy45
... The AC is moving heat that is inside the cab, to the outside -- at the condenser. All of that heat ends up near the engine (which is also under additional load from the compressor), so a small rise in temps seems OK.


Originally Posted By: KrisZ
The condenser is in front of the radiator, so when you turn on the AC, the hot air coming off of the condenser goes through the radiator next. In effect it reduces the heat removal capacity from the radiator a little bit, hence the increase in the temperature.


These easily account for the few degree change you're seeing. Drive on.
_________________________
Thick vs Thin test: 15k / 43k miles complete

Top
#4503745 - 08/31/17 07:23 PM Re: Running Hotter with A/C [Re: WyrTwister]
another Todd Offline


Registered: 05/15/06
Posts: 2205
Loc: Lakeside CA
Originally Posted By: WyrTwister
Is the gauge showing HOT ?

Have it boiled out any coolant ?

Here is my take on this . As long as the coolant is at least 50% - 50% and is circulating properly , you will not damage the engine if it has not boiled off any coolant .

Am I right ?


In terms of boiling off coolant, the radiator pressure cap is much more important than coolant/antifreeze. Roughly, for each pound of pressure the system holds, the boiling point goes up 3 degrees. So a 15 lb. cap in good condition won't allow water to boil until roughly 255 degrees if no leaks in the system.

In terms of doing engine damage from overheating without coolant boiling over, yes it is possible.
_________________________
2015 Ford F250 Diesel Crew Cab FX4
2017 Ford Escape 2.0
2002 GMC Yukon
2015 Hyundai Accent
2008 Yamaha Rhino 700 FI

Top
#4503761 - 08/31/17 07:37 PM Re: Running Hotter with A/C [Re: Nick1994]
WobblyElvis Offline


Registered: 09/23/14
Posts: 1350
Loc: Toronto Canada
There is nothing wrong with the Jeep. Under more load it runs hotter.

Top
#4503797 - 08/31/17 07:59 PM Re: Running Hotter with A/C [Re: Nick1994]
Merkava_4 Offline


Registered: 01/30/07
Posts: 17501
Loc: Clovis, CA
Originally Posted By: Nick1994
It also has an electric fan


You need two large electric fans with two speeds. Low speed comes on at 216F and high speed comes on at 221F. With A/C on, it automatically defaults to high speed.

I drive around town with the A/C on and water temp is at 176F. Ambient over 100F.

Top
#4503809 - 08/31/17 08:06 PM Re: Running Hotter with A/C [Re: Nick1994]
Nick1994 Online   content


Registered: 02/19/13
Posts: 10123
Loc: Phoenix, AZ
So 230 degree spikes are no issue?

I have major concerns of off-roading in the desert and overheating in the middle of nowhere. Or pulling my small trailer in the mountains and getting too hot.

For comparison a customer of my mechanic's has the identical Jeep, same year, even same color! His is almost always 195 degrees, same gauge.
_________________________
2015 Hyundai Sonata 2.4L 79k PU 5w30 & OEM
2000 Toyota Camry 2.2L 228k M1 AFE 0w30 & Wix
1996 Jeep Cherokee 4.0L 146k M1 HM 10w40 & Fram Ultra

Top
Page 1 of 5 1 2 3 4 5 >