temp raise after 15 min drive with AC on, but go back if i turn off AC

[rolo95]

Guys,
normally my temp gauge sits a tick below the 210 mark or at the 12 noon ( 210 mark) on very hot days in south TX
but recently if i have the AC on, it starts to climb to 2 ticks above the 210 mark
if i turn the AC off it goes back to the 210 mark after like 5-8 mins drive.

does the coolant type really matter ? i mean the green vs the orange type.
the A/C radiator or engine radiator or both dirty ?
bad clutch ?
bad thermostat?
all of above ?

Thanks
Rolo.

 

[TollKeeper]

You didnt mention what year truck you have.. That can make a difference for the fan.

It could be the fan clutch
It could be the thermostat

Cooling systems have a lot of parts.. and ports. It could even be a blocked coolant passage(s).

Check and make sure the radiator is full, and that the overflow is full. From there, I dont have a good guess really.

My Envoy starts to creep up on the temp if I am idling for a long (LONG) time. But my AC also isnt staying as cool. So I know its either a blocked condenser (bug guts, dirt), or a bad fan clutch. I just dont let it idle that much anymore. Its got AC that will freeze you out if your driving above 35mph thou! I think its a clutch problem for me. I just have not gotten around to sending the PCM out for a tune, so I can put in a 08-09 fan clutch.

 

[rolo95]

02 TB
i did not type it cause it is on my profile

 

[Reprise]

Just a quick note to answer your question about conventional antifreeze vs. Dexcool...

You're basically OK with either, from a temperature management standpoint, but you CANNOT mix them together. To switch over, you MUST completely empty the cooling system (including the engine block) before introducing the other coolant (either way).

If you have done this (topped off with green, etc.) -- you need to get the existing coolant out ASAP, flush with water until it comes out clear, and then (completely) drain / fill with the coolant of your choice.

PS: Dexcool (unadulterated) allows for a longer change interval, vs. conventional green -- but it's still good practice to change it out every 3 years. Drain / refill is fine for this; if you've been changing it out on the regular, you don't need to flush it, unless you detect corrosion in the system.

 

[rolo95]

Haa! , did not know that, so i think i will try a flush 1st and see what happens...
Btw, how you clean the coils from the outside

just soapy water ?
or you need like those A/C service guys solvents to clean the evaporators coils on office A/C units.

 

[Reprise]

A garden hose with a good high-pressure setting on the nozzle will flush out the condenser. Shouldn't need soap.

If you don't have access to a garden hose, take the vehicle to a self-service car wash, and put the selector on 'rinse'. That should provide a good pressure stream to remove the junk from the condenser. Pop the hood before you put the money in

Also, if you have a plastic shield in the engine compartment blocking access to the top of the condenser, take it out, along with the grille, to give yourself unrestricted access.

 

[Mooseman]

Sounds to me like the fan clutch. To test it:

How to test the electro-viscous fan clutch

 

[rolo95]

Sounds to me like the fan clutch. To test it:

How to test the electro-viscous fan clutch

What about the fan clutch relay, I'm ordering the lowlights one, so maybe time to order 2 and replace both.

I don't get an engine light on error, is that normal even if the clutch is failing?

 

[aaserv]

The speed of the fan clutch is determined by 2 things mainly. Water temp and A/C head pressure. If yours is an 02 then for sure unless the fan speed settings have been updated it turns to slow. Youll need to find a shop that can set the speeds via the computer. I spent 3 years trying everything under the sun but getting the computer adjusted a few weeks ago was maybe all I ever needed. Mooseman has posted a chart before showing the recommended settings but living in the deep south heat belt Im pretty sure they set mine even faster than those recommended settings.

I do still believe that the cheaper fan clutches do not respond fast enough to the computer telling it to increase the speeds. But on the early models 02-04/05 it doesnt tell it to spin fast enough anyway. Apparently this was done to keep drivers from complaining about the noise the higher fan speeds make and to increase gas mileage. Since getting mine done I do hear the fan (a lot!) but havent noticed yet any decrease in gas mileage... The noise is well worth it . I can drive in heavy traffic now with the A/c wide open and my needle never moves from 209 degs..

I never got a ck engine light with any of my problems with overheating...

 

[Mooseman]

Codes for the fan clutch are iffy at best. I think the only time they actually work is when it's unplugged and when it's locked up and sounds like a dump truck.

For the relay, yes it's the same as the headlights however, if you choose to replace them, get OEM. The aftermarket ones tend to fail.

 

[Mooseman]

The one for the fan clutch rarely fails because it's lower amperage than the headlights. You could try swapping them to see if they still work.

 

[TJBaker57]

 

[rolo95]

Thanks All , let me see what happens with the rag fan test.

 

[rolo95]

Ok, engine hot, ac on, rag stop method...
I can easily stop the fan and no tugging/pulling from the clutch...so I guess the clutch is gone...

What brand is the less worst from all the options...
Rock Auto?

 

[Mooseman]

Best is ACDelco/Behr, which is the original. RA don't seem to have them anymore. Second best would be Hayden. Look for a thread in the FAQ in my signature that talks about clutch quality.

 

[MD_Envoy_Driver]

Ok, engine hot, ac on, rag stop method...
I can easily stop the fan and no tugging/pulling from the clutch...so I guess the clutch is gone...

What brand is the less worst from all the options...
Rock Auto?

Bought one from NAPA. It lasted 8 months. Got a replacement from Rockauto. Seems to be holding its own. It has a massive heat-sink compared to the NAPA one and runs the width of the clutch. I was very angry to see how cheap the NAPA one was built and they really skimped on everything.

 

[rolo95]

Bought one from NAPA. It lasted 8 months. Got a replacement from Rockauto. Seems to be holding its own. It has a massive heat-sink compared to the NAPA one and runs the width of the clutch. I was very angry to see how cheap the NAPA one was built and they really skimped on everything.

From Rock Auto what brand of clutch u got

 

[MD_Envoy_Driver]

GM GENUINE 1540133 (Electronic) Info

Includes Sensor

I cut and pasted this from my RockAuto order page. They appear to be currently out of stock. The INFO lettering will take you to the part I ordered.

 

[JayArr]

I recently drove home through the mountains with a trailer while monitoring the coolant temperature using Torque Pro.

Running the AC raised the coolant temp 5-7C. (8-12F). The engine ran at 92C (198F) without AC and went up to 99C (210F) with it on.

AC takes a lot of energy and raises the coolant temp by a significant amount.

You may be chasing your tail here, if you think you can fix the cooling system so that the temp doesn't go up when you run AC then you may be disappointed.

Before you guess or throw parts at the problem get a ODBII module for $10 from Amazon and load Torque Pro onto a phone and then monitor things for real. You can watch the coolant temperature much better - the guage in your dash is not at all accurate. You can also monitor the fan "requested speed" and "actual speed" to see if it's doing it's job. Without good data you could easily spend $500 and still have coolant that still gets hotter when you turn the AC on.

 

[MD_Envoy_Driver]

For what it's worth... after putting the AC/DELCO fan in, even in the hottest of days in Maryland (95 degrees or so) and the AC on, the needle never gets past 210 even in heavy stop-and-go traffic. It usually stays two tick marks below if I am just cruising along.

 

[MD_Envoy_Driver]

GM GENUINE 1540133 (Electronic) Info

Includes Sensor

I cut and pasted this from my RockAuto order page. They appear to be currently out of stock. The INFO lettering will take you to the part I ordered.

Apparently these are back in stock at RockAuto (for now)

 

[aaserv]

For future reference, if you do a google search on the GM part number you will find quite a few GM Dealers and others who have the original BEHR unit on their shelves although not at Rock Auto prices.
Before buying I would call them and make sure this is New/Old stock and not just some cheap knock off they are selling as the original since its NLA for the most part. Worth a shot!