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Ok about a week ago my dumb ass forgot to put the radiator reserve cap on ,was on the freeway and yes the water started to exple so I pulled over immediately it didn't go into limp mode,it got alittle warm,anyways filled it up went home. Everything was fine then I noticed the temperature gauge was not moving,stuck at 160? Wtf....so I checked everything,I even put a new thermostat in as I had an extra one,now it's throwing a p0125 &p0128 code,and now when I go to start it it's sounding like it's starving for fuel,and the temp gauge will not go past 160.I put a laser thermometer on the hoses they read about 185 so what do I do
 

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2006 Escalade AWD w/DiabloSport tuner,Jet Performance throttle body/MAF,Airaid MIT
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1,651 Posts
Best guess is that air is in the system when the coolant poured out the reservoir when the top was off. I would remove the coolant reservoir top with the engine running in park to allow the trapped air to bubble out the system.
 
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2004 Escalade 6.0
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1,232 Posts
Wouldn't air in the system cause it to overheat not run too cool?
 

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'93 SedanDeville 60 Special
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813 Posts
The reason the engine would run like crap is
PCM is expecting from a cold start that coolant temp would be over 160 deg within like 10 minutes timeframe
if not over 160 then PCM then it will stay on open loop and ignore the feedback sensors and run in speed density/ VE mode, so ignores MAF, O2 sensors, etc

Using OBD-II scanner see what coolant and air temp is being reported
See if engine is staying in OPEN loop or is going to closed loop

Is it possible when coolant ejected that it got onto the relay for the coolant fan and fan then is running all the time even when the engine is cold so never gets hot enough

Is it possible the coolant got onto wiring for the ECT sensor and is lying to PCM ?
as sensor is putting out a resistance value and coolant on wiring or pins could cause incorrect reading ?
The fact your temp reading was 185 deg and not 160 I would start with the ECT sensor and wiring connector/pins

Is it possible to add to the problem that the new Tstat put in is really a 160 deg set opening ?
 

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2003 Escalade ESV
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Hey guys, chiming in here since I seem to have the same problem, or at least very similar. I bought a 2003 Escalade ESV about a month ago, and the temp gauge never gets above the mark between 160 and 210 (so I'm guessing it's about 180° or so). For reference we've had a 2002 Suburban, so the 5.3 in that one instead of the 6.0, which always ran right around the 210° mark.

I figured the Caddy had a bad temp sensor for the gauge, but a couple days ago I got a P0128 code for low coolant temp. I replaced the thermostat today, both the new one and the original were the oem 187° temp range, but the temp gage still doesn't read above 180 or so.

Do these have separate sensors for the gauge and the PCM, or does it work off one sensor? I don't have an easy way to measure actual engine temp, so maybe I just have a bad sensor? Seems unlikely if there are two sensors though.

Can any of you tell me where the sensor(s) is?
 

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02 Escalade,96 Aurora,with Shelby engine
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do yourself a favor and spend $30 on an IR temp gun
you will find many uses for it.
Read right at the thermostat housing and at the radiator hose inlet(metal part)on the radiator.
 

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'93 SedanDeville 60 Special
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813 Posts
Is the cooling fan(s) electric or driven off the water pump/crank ?

If manual fan then maybe the clutch of fan has a problem and is rotating sooner than it should causing the average temp to be cooler

If electric :

Is it possible someone in the past tuned the PCM and set the fans to come on sooner ?
From a cold start monitor the coolant temp and fan rotation, find out at what temp the fan begins to rotate
and report what that temp is

Again if electric and was tuned if looking at a GM tuning calibration you see the PCM normally does not command fans on until 220 deg and even then only about a 10% rotation, as temps go higher than PCM commands higher and higher rotation
PCMs I tune and owner wants cooler ECT and depending on the opening of Tstat installed I go into that table and command fan to come on sooner and at higher rotation speeds

Should be only ECT temp sensor in engine block, many times close to cylinder #1
As mentioned get an IR temp tool and map out temps including right by that sensor

Rectangle Font Parallel Screenshot Technology
 

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Magoo—2012 Cadillac CTS Luxury, Opulent Blue, plus many more, see signature.
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524 Posts
@Yondering , I'm going to agree with @parts68 that you really need to use an infrared thermometer to get the actual temperature at the thermostat housing.

You should also use an OBD-II scan tool or scan app with an OBD-II dongle to read the coolant temperature data from the PCM. I think the 2003 with the 6.0L engine only has one sensor for the PCM, and the PCM controls the gauge in the cluster. That doesn't mean that the gauge is always accurate. But getting the actual temperature reading from the PCM can explain why the P0125/P0128 codes are getting set if you seen those.
 
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