5.3 LS swap: cooling issue (formerly a kinked upper hose) (1 Viewer)

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I wonder if there isn’t a completely different issue. If it can sit and idle and not run hot, then it seems the radiator and fan are moving enough air to maintain temps. If it heats up as you are driving with even better air flow, is it possible that you are running lean? Any dash lights on, curious when you get the gauge on what that will tell you.
 
I wonder if there isn’t a completely different issue. If it can sit and idle and not run hot, then it seems the radiator and fan are moving enough air to maintain temps. If it heats up as you are driving with even better air flow, is it possible that you are running lean? Any dash lights on, curious when you get the gauge on what that will tell you.


No dash lights...and to clarify, it will eventually run hot just at idle, did it yesterday when I was burping the system...seems to very with outside air temps. It's been in the 30's-50's most days I've been tinkering with this
 
No dash lights...and to clarify, it will eventually run hot just at idle, did it yesterday when I was burping the system...seems to very with outside air temps. It's been in the 30's-50's most days I've been tinkering with this

...My temps are sitting at about 1/2 sitting at idle when driving it will rise to 3/4 or slightly higher on the dash.

Okay, maybe worth editing your #11 post so people don’t come to the same conclusion I did.
 
that hose is one gipsy setup big time if you went 90 degree from throttle body and 45 degree it will match perfectly to air box
and you can use GM OEM coolant hose with no problems i have apsolutnu no clearance problems
<a href="https://ibb.co/gTsBSG6">IMG-3189
I kinda like seeing household plumbing products and plenty of either electrical or duct tape on my motor swaps, but that is just me. 😉

Is that a residential gas line fitting or for water?
 
UPDATE: suggestions pleaae...

Truck is not HOT. 197 was the best I saw today after to minutes in town, hillls, stop and go. Its 40 degrees out.

Based on that, that temp gauge should be dead from 180-220 (or is it 210?), so why is the temp gauge moving to 3/4?

Not a cause for concern, however the toyota temp sensor and gauge are somehow sensing an overheat and are shutting down my AC system.

I have yet to find the temp gauge on this thing...could it be a bad sensor? Do I just unplug it and run the torque app? Do I replace it with a chevy? Is there a way to calibrate it?
 
UPDATE: suggestions pleaae...

Truck is not HOT. 197 was the best I saw today after to minutes in town, hillls, stop and go. Its 40 degrees out.

Based on that, that temp gauge should be dead from 180-220 (or is it 210?), so why is the temp gauge moving to 3/4?

Not a cause for concern, however the toyota temp sensor and gauge are somehow sensing an overheat and are shutting down my AC system.

I have yet to find the temp gauge on this thing...could it be a bad sensor? Do I just unplug it and run the torque app? Do I replace it with a chevy? Is there a way to calibrate it?


I think you need to figure out where the temp sensor is on your motor and then disable it and figure out the wiring so you can have reliable AC. I am no wiring expert, but it seems like the way the gauge and the sensor are reacting to each other is telling the ECU that you are overheating, even though you aren't.

Good luck. It's this type of thing that prevent louts like me from going down the rabbit hole and just stay safe with our stock power platforms.
 
My initial thoughts are to leave the tota gauge as its supposed to he dead/dummy from180-220.

Are there multiple sending units? As the PCM is sensing and sending 197 to the OBD ii...but the gauge is either reading incorrect or getting a higher temp.

What to do next?

Also, 197 seems running cool for a chevy...that's next on the list to address.
 
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Usually the temp sensor on a swap will be at the rear of the passenger side head.
 
If you are running the Toyota temp sensor, I would be very surprised if it is wired into the Chevy ECU. The Chevy ECU is usually what controls the AC. If you have a Chevy sensor, I have no idea how the Chevy signal, will be interpreted by the Toyota gauge.

whether Toyota or Chevy sensor, the dash gauge is controlled by a single wire directly to the connector behind the glove box. See pin 2 of the IH1 connector

Bottom line, you ARE NOT over heating, your AC issues are not related to temp issues, and your only temp issue is an accurate monitoring ability?
 
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If you are running the Toyota temp sensor, I would be very surprised if it is wired into the Chevy ECU. The Chevy ECU is usually what controls the AC. If you have a Chevy sensor, I have no idea how the Chevy signal, will be interpreted by the Toyota gauge.

whether Toyota or Chevy sensor, the dash gauge is controlled by a single wire directly to the connector behind the glove box. See pin 2 of the IH1 connector

Bottom line, you ARE NOT over heating, your AC issues are not related to temp issues, and your only temp issue is an accurate monitoring ability?


50% correct...NOT overheating, however the dash cluster seems to think so...the AC will run when the dash gauge reads normal range. As the dash temp gauge reads hot, AC shuts off (but you're saying the chevy PCM is shutting it off?)...yet truck is still reading 197 max temp on an OBD II reader with data that is coming from the chevy PCM...so in theory the PCM should not be sending an overtemp signal and shutting down the AC?

No dash lights, no CEL, nothing.

is there a way to get this yota sending unit and dash gauge to read correctly again? Do I need to get into HP tuners? I'm fine running Torque App to monitor, but would like to stop the yota side from thinking its overheating, when its not.
 
In my opinion you have two different & unrelated issues.

PCM functionality and dash gauge calibration

Dash gauge calibration
Confirm you have a Toyota sending unit. It will likely either be located in your top radiator hose or on the PS head. Stand at the PS fender, and look at the firewall end of the head. You will either see a plug filling a port to the water jacket, or a Toyota sender. More knowledgeable folks can chime in, but if you do not see a sending unit in either spot, your Toyota gauge, will be reading the Chevy unit, they are calibrated differently, and the gauge will never read correctly. You can back track to the sending unit by poping out the glove box, and backtrack the wire plugged into Pin 2, on the IH1 connector back through the firewall into the engine compartment.

PCM programming
This may take a professional more familiar with the LS engine & programing. OBDII reading should be the same as what the PCM is reading. I think the OBDII gets its data from the PCM not the sender. So if you are getting OBDII 197, and AC is shutting off, it’s an AC issue or perhaps the programming needs to be adjusted

But I am far from an expert. Veteran of one LS swap, and live in AK, and know even less about AC.
 
Dash gauge calibration
Confirm you have a Toyota sending unit. It will likely either be located in your top radiator hose or on the PS head. Stand at the PS fender, and look at the firewall end of the head. You will either see a plug filling a port to the water jacket, or a Toyota sender.

Coy all on the AC issue...

I found a tempsending unit on the #1 cyl head (DS front behind the alternator)

is there two, you're saying, or a second unit is required, one to PCM and one to gauge? this motor is an '04 5.3 from a tahoe
 
Coy all on the AC issue...

I found a tempsending unit on the #1 cyl head (DS front behind the alternator)

is there two, you're saying, or a second unit is required, one to PCM and one to gauge? this motor is an '04 5.3 from a tahoe

I would wager that is the factory Chevy sending unit, providing data to the Chevy PCM. (Google search of some kind, could probably confirm). But yes, if you want to use the Toyota dash gauge, you will need two sending units. A Chevy unit feeding the Chevy PCM, and if you want to use the Toyota dash guage, you will need a Toyota unit, sending the signal it is calibrated to receive.

The Chevy PCM would loose its mind if it received a signal from a Toyota sender. Likewise, your dash guage will not be correct, if it is receiving a signal calibrated for a Chevy gauge.

As I have mention in previous post. Pop the glove box out, and follow the wire connected to pin 2, back through the fire wall, and see where the dash signal is coming from.
 
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I would wager that is the factory Chevy sending unit, providing data to the Chevy PCM. (Google search of some kind, could probably confirm). But yes, if you want to use the Toyota dash gauge, you will need two sending units. A Chevy unit feeding the Chevy PCM, and if you want to use the Toyota dash guage, you will need a Toyota unit, sending the signal it is calibrated to receive.

The Chevy PCM would loose its mind if it received a signal from a Toyota sender. Likewise, your dash guage will not be correct, if it is receiving a signal calibrated for a Chevy gauge.

As I have mention in previous post. Pop the glove box out, and follow the wire connected to pin 2, back through the fire wall, and see where the dash signal is coming from.

You the man, thanks
 
And now the friggen radiator seems to be leaking. Wondering if that is getting some air in the system and causing the toyota side to think its warm.

The GM PCM get a 192/194 degrees.

Cannot find the leak...upper lower hose look great/dry, over fill bottle is clean, water pump area is dry. Just seem to have drops on bottom of frame in the front, below the protective cover for the fan. I've crawled all over and cannot find it.

Am I missing anything or next step is having the radiator pulled? It's a newer 4 core aluminum radiator, not sure the brand, but I wouldnt expect it to have cracked
 
I do not understand the physics behind it, but a pressurized system helps the engine run cooler.

If the cooling system cannot hold pressure, it will run hotter.
 
what I used in a FJ 60 with a champion top/bottom flow radiator top hose napa NBH ff242 & NBH 9867 with an ICT Billet hose connector with steam port AM627-21X125, bottom hose NAPA NBH 7486,
with the ICT Billet thermostat housing adapter 551491 and a Summit 90* thermostat swivel neck.
 

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