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Well thats better than before. Are you getting heat both sides in the cabin?
Is the coolant reservoir maintaining its coolant level?
1 1/2 miles is not far especially if outside air temp is low.
Agreed. I corrected a mistake in my last post. Operating temp should be 215 degrees and that's when a 195 rated thermostat would be fully open and temp should be the same on each side of the stat. You need to run it longer and get it to normal operating temperature.
Sorry for the delay...Had to quit for a couple days due to Thanksgiving!
Sean (and team) I replaced the thermostat and took it for a test drive (3-4 miles) and no problems...then I let it cool down and checked the radiator fluid level. Its was a little over the "max" in the reservoir. I left it alone and took it on a 2nd test drive (6-8 miles) and it never overheated. It set outside overnight and I thought it was fine until I drove it this morning. I went to eat breakfast (4 miles away) and no problems...but when I headed home it started to climb in temp. I gave it some gas and took my speed up to 65 mph from 45 mph and it cooled down. I drove for 3-4 more miles and then it started to overheat again. I pulled over and popped the hood. I could see that there was some antifreeze around the expansion tank cap. No leaks in any of the hoses. it appeared to come from the cap.
The various temps at the time I stopped are below:
upper hose 195
lower hose 117
in front of thermostat 207
behind the thermostat 174
Could it overheat if there is to much radiator fluid in it?
A previous post stated that the reason there was could air in the cabin on the driver side and hot air blowing on the passenger side was because one of 2 auxiliary pumps are going out. Could that be a reason for bad circulation? therefore causing it to overheat?
Really thought that the new thermostat was bad, and replacing it fixed the problem...but apparently there's something else contributing to the overheating.
No it won't overheat because of too much coolant but it could overflow if you initially filled it above the fill mark. What's your evidence it's overheating?
Temp on the outlet of the thermostat should be the same as the inlet. In your case at the time you took it, 207 on both sides.
From the service manual:
The thermostat is located in the thermostat housing and allows rapid engine warm-up by restricting coolant flow through the radiator below 82°C (180°F). The thermostat also assists in keeping the engine operating temperature within predetermined limits. On the 4.2L supercharged engine the thermostat begins to open at 84°C (183°F) and is fully open at 98°C (208°F), on the 3.5L or 4.2L and 3.0L engine the thermostat begins to open at 88°C - 92°C (190°F - 198°F) and is fully open at 102°C (216°F). When the engine is cold and the thermostat is closed, coolant flows from the water pump through the engine. It then returns to the water pump through the upper coolant hose. When the engine is warm and the thermostat is open, coolant flows into the radiator through the upper coolant hose. It then returns to the water pump from the radiator through the lower coolant hose and engine oil cooler.
The heater core is on a parallel circuit and is unaffected by the position of the thermostat.
The Auxiliary pump pushes coolant through the heater core and as noted above, is on a parallel circuit and unaffected by the thermostat. It's easy enough to check as you can check the temps on the inlet heater hose and outlet heater hose. You can also reach it (CAREFULLY) and feel it running. The supercharger pump is the other coolant pump. Lastly of course is the water pump which again is easy enough to check with an IR thermometer.
Got it...so technically it should never go over 208ish if the thermostat is rated for 183. Do you think maybe its having trouble circulating due to a bad auxiliary pump?
Got it...so technically it should never go over 208ish if the thermostat is rated for 183. Do you think maybe its having trouble circulating due to a bad auxiliary pump?
I edited my post to update some info about the two aux pumps and the water pump. You should be using the 195 rated thermostat for the supercharged engine.
I think at this point, you should provide us with codes and also confirm why you think it's overheating. The temps are within range.
Check that. Temps are not normal. Thermostat outlet temp must be a misread. It should be 207 as well. Otherwise the upper radiator hose wouldn't be at 195. There is no circulation to the radiator until the thermostat opens and allows the water into the water pump.
That said, all of the temps you mention are within spec.
Got it...so technically it should never go over 208ish if the thermostat is rated for 183. Do you think maybe its having trouble circulating due to a bad auxiliary pump?
The auxiliary pump ( the heater core pump) if not working will cause lack of heat in the cabin.
It also plays a role in the coolant fill process by sucking coolant out of the coolant reservoir. It is right below the bottom connector of the coolant reservoir.
If it does not do this then possibly an air pocket in the heater core which will cause lack of heat in the cabin.
The supercharger pump pumps coolant thru the charge coolers either side of the supercharger. It is not usually referred to as an "auxiliary pump".
Sean W - I'm waiting for a call to meet a friend that can pull the codes...I've loaned mine to my brother and haven't received it back.
The only evidence I have of the "overheating" is based on my temp gauge needle on the dash moving up toward the RED suddenly. But I immediately stop and pull over and get a temp reading with my IR thermometer...so far it's been no higher than 209 on the upper hose, and then 174 around thermostat, and then down by bottom hose it's 117.
I'll post the codes shortly...and thanks again for walking me through this.
Sean W - I'm waiting for a call to meet a friend that can pull the codes...I've loaned mine to my brother and haven't received it back.
The only evidence I have of the "overheating" is based on my temp gauge needle on the dash moving up toward the RED suddenly. But I immediately stop and pull over and get a temp reading with my IR thermometer...so far it's been no higher than 209 on the upper hose, and then 174 around thermostat, and then down by bottom hose it's 117.
I'll post the codes shortly...and thanks again for walking me through this.
OK well I thinks that's good news Steve. We'll wait for the codes but if your gauge is moving up suddenly and you're stopping immediately and reading normal temps, you may simply be left with a gauge problem, having already solved the thermostat problem. Others should chime in but I've never had a car of any kind go from overheat to normal within such a short time period.
Regarding the coolant smell, it can linger in the engine bay for a year. If you remove the underside cover, take it to a car wash and power wash it clean. inspect the underside of the engine for leaks. Check along the transmission tunnel as that where the valley hose usually shows first signs of failure.
Anyway, my point is you may have fixed your primary issue and now chasing ghosts so a good cleaning can help rid the smell and while you're under, do a visual inspection.
Once the codes are clear and your confident you've fixed the overheat issue, open a new thread on the auxiliary heat pump and heater core. That's a different animal. There are several threads on the pump and the heater core. Let's hope it's the pump. DO a search on that and start a new thread about it if you don't mind.
P0037 HO2S heater control circuit low (bank 1 sensor 2)
P0057 …...................................( bank 2 sensor 2)
P1646 *Heated O2 Sensor Fault bank 1 problem
P1647 upstream oxygen sensor on bank 2 problem
P1582
P0102 mass or volume circuit low input
P0111 intake air temperature circuit range/performance problem
P0112 intake air temperature circuit low input
P0117 engine coolant temperature circuit low input
P1582 DTC P1582 (Flight recorder) data is stored if any one of the five conditions listed below occur:
1. Inertia switch activated.
2. Throttle failure causes default into limp home mode.
3. Engine starts and stumbles.
4. Engine fails to start.
5. Engine stall.
Only 1 of the error codes refers to coolant.
When you replaced the thermostat I presume you took off the air inlet pipe? Did you disconnect the MAF sensor with no problem and reinsert with no problem?
Others more knowledgeable will chip in I hope but I was wondering if the MAF sensor is disconnected or screwed up in some way could
it cause other problems with say the O2 sensors?
When you replaced the thermostat I presume you took off the air inlet pipe? Did you disconnect the MAF sensor with no problem and reinsert with no problem? Yes i had no problems.
See my post 13. Did you check the ECT sensor? P0117 implies a problem there. You could do what many do and clear these codes and then see which ones return. We have no way of knowing if repairs were made but codes not cleared (never likely but if your friend will clear them at no charge...) Here are the tests for P0117.
G258127t8 : CHECK THE ECT SENSOR SENSING CIRCUIT FOR HIGH RESISTANCE 1. Disconnect the battery negative terminal. 2. Disconnect the ECM electrical connector, PI01. 3. Disconnect the ECT sensor electrical connector, PI25. 4. Measure the resistance between PI01, pin 70 (UY) and PI25, pin 02 (UY). Is the resistance greater than 5 ohms? -> Yes REPAIR the high resistance circuit. For additional information, refer to the wiring diagrams. CLEAR the DTC. TEST the system for normal operation. -> No GO to Pinpoint Test G258127t9.
G258127t9 : CHECK THE ECT SENSOR SENSING CIRCUIT FOR SHORT TO HIGH VOLTAGE 1. Reconnect the battery negative terminal. 2. Turn the ignition switch to the ON position. 3. Measure the voltage between PI25, pin 02 (UY) and GROUND. Is the voltage greater than 3 volts? -> Yes REPAIR the short circuit to high voltage. For additional information, refer to the wiring diagrams. CLEAR the DTC. TEST the system for normal operation. -> No GO to Pinpoint Test G258127t10.
G258127t10 : CHECK THE ECT SENSOR SENSING CIRCUIT FOR SHORT TO GROUND 1. Turn the ignition switch to the OFF position. 2. Measure the resistance between PI25, pin 02 (UY) and GROUND. Is the resistance less than 10,000 ohms? -> Yes REPAIR the short circuit to GROUND. For additional information, refer to the wiring diagrams. CLEAR the DTC. TEST the system for normal operation. -> No INSTALL a new ECT sensor.
Engine Coolant Temperature (ECT) Sensor - 4.2L NA V8 - AJV8 (18.30.10) CLEAR the DTC. TEST the system for normal operation.
P0037 HO2S heater control circuit low (bank 1 sensor 2)
P0057 …...................................( bank 2 sensor 2)
P1646 *Heated O2 Sensor Fault bank 1 problem
P1647 upstream oxygen sensor on bank 2 problem
P1582
P0102 mass or volume circuit low input
P0111 intake air temperature circuit range/performance problem
P0112 intake air temperature circuit low input
P0117 engine coolant temperature circuit low input
P1582 DTC P1582 (Flight recorder) data is stored if any one of the five conditions listed below occur:
1. Inertia switch activated.
2. Throttle failure causes default into limp home mode.
3. Engine starts and stumbles.
4. Engine fails to start.
5. Engine stall.
Only 1 of the error codes refers to coolant.
When you replaced the thermostat I presume you took off the air inlet pipe? Did you disconnect the MAF sensor with no problem and reinsert with no problem?
Others more knowledgeable will chip in I hope but I was wondering if the MAF sensor is disconnected or screwed up in some way could
it cause other problems with say the O2 sensors?
Yes I believe the fuel trims are impacted and can trip the O2 codes. I would check vacuum lines, the entire air induction for cracks, gaps etc. I'd clean the sensor with specific MAF sensor cleaner (not carb cleaner).