Running warm condition

My 07 3.4 torrent runs warm when not moving. Any speed above 1200 rpm and temp gauge never rises. The cooling fans are running. Ac works fine. I have had it for 1 yr. I think it has a slight headgasket issue as system stays pressurized after 12 hrs. I do not use any coolant. I think it is poor coolant flow at idle due to air blockages? If I raise idle to 1500 rpm the temp needle will drop to normal. Could it be a worn waterpump? Is this a flow issue? Due to what?

Yes it could be a water pump issue.
But as an 07, I would pull the radiator and have it flow tested. Alternately, check radiator for hot and cold spots.

Suggest to start by your shop performing a head gasket test. If you have that problem, pretty much have to fix that first before exploring other overheating causes.

If there’s some reason you just don’t want to have that test done, common overheating at idle causes are

  • cooling system not operating at the correct pressure. could try replacing the pressure cap.
  • thermostat not working correctly. could try replacing the thermostat.
  • water pump not working. could try replacing the water pump
  • radiator clogged, could try replacing it.
  • engine timing problem (either too advanced or too retarded)
  • a/f mixture problem (too lean)

I do have new wp.on shelf. Drive 30mph, rock solid temp gauge. Stop at light, it ticks up past 1/2-way. Pop it. In neutral, rev to 1200-1500, goes down to normal.Green light, gauge goes down to normal. Drive 30 miles at 55? Smack dab in normal range. Never moves.

To me, that sounds like a radiator problem. If you have a infrared thermometer you can check for hot&cold spots.
Rockauto shows new radiator $124.

i fix equinoxes on the side. headgasket issues.
It had lack of heat issues this winter.
Flushing heater core did not help it.
Always something.

Sometimes temp gauge reads cold and does not move.
Next time I use car, it works normal.
At stop, temp will rise, start moving, right back to normal.
At drive thru today I got engine hot message, ac off
It always does that at drivethru. Ac is on, fans are on
Started driving and gauge went back to normal. Ac is on.
Is motor really hot?

Whenever I’ve had the drive-through overheating problem, it has always been that the radiator fan isn’t turning on at the temperature it should. Double check next time it happens, leave the engine running, get out, pop the hood, are the radiator fans spinning like crazy? I’ve had to replace the radiator fan-on temperature switch two or three times over the years. That part is the most finicky part of all the parts of my Corolla.

The heater core gurgle is a bad sign. Coolant reservoir was almost full last month. I sucked out 16oz and a day later it was 1” below cold fill line. I poured coolant back in to fill line. Yesterday it was full to top again. So, I’m thinking big air pocket in system? From headgasket? Since I have done the job on 3 other equinoxes I know how to do it. Do I want too?

On a 2008? Of course, fix it right. That means replace the radiator, radiator hoses, heater hoses, thermostat, water pump, etc. And if doing a head gasket, have the head reconditioned by a professional machine shop. Don’t cheap out on a job like this.

Was leaning towards airflow as driving over 20mph keeps temp at normal. But today I noticed, when stopped if I raise rpm to 2k, the temps drop back to normal. So, it’s a Coolant flow issue. Not air thru radiator. Fans work fine. Ac on, fans on.

have you checked radiator cap or overflow cap?

I have a equinox and torrent and both have same motor. I will try using #2 cap on #1 car.
But, if it’s really a head gasket issue, raising rpm to 2k should usually make no difference. Driving at 50mph never overheats. Gauge stays at normal all the time. It’s only when idling.
My 03 vue uses same rad cap. As does equinox, as does torrent

Old pump looks fine. New pump leaks. What the bleep?image

When it’s allegedly overheating have you check the reported temp with an OBD scanner, or infrared thermometer at the top rad hose fitting?
Any other signs it’s actually overheating, like a boil over?
It could be a faulty gauge.

Guy at work had a car that would immediately overheat (the temp gauge would suddenly spike) at idle. If we revved the engine, it would go back to normal. We checked the temp with a IR thermometer and it wasn’t overheating. We removed the radiator cap, started the engine, and it puked coolant violently out of the filler kneck. So, we believe he had a head gasket leak with exhaust entering the coolant passages. I believe air pockets caused the temp gauge to spike. At idle, I assume the air pocket got up around the sensor for the temp gauge. Then when you revved the engine, the coolant would flow past the temp sensor and the gauge would read normal. One of his radiator hoses (bottom, I think) had a fair amount of pressure on it at cold idle also.

What you’ve got going on sounds a little similar, although probably not as obvious. Sounds like an air pocket, but if you’re certain you’ve bled the system well…could be a little exhaust gases getting forced into the water jacket from a head/head gasket issue.

Is there a way to pressure test the system with the engine running to see if it’s getting more pressure than normal? Honest question, I’ve never had a pressure test done on anything.

The bolts for waterpump are 5/16” hex so I used a 1/4” drive ratchet. Torque is 89in/lbs or about 7 ft/lbs. ya think using a 1/4” ratchet might change feel for bolt tightness vs 3/8”? No, I don’t have an inch torque wrench.

I doubt there’s much difference in the feel for 7 ft pounds, comparing a 1/4 inch drive vs 3/8 inch drive ratchet. If there’s a difference in the amount of torque applied, seems more likely related to the longer handle on the 3/8 ratchet. When I’m doing something like that I’ll take the bathroom scale out to the garage and push on it until it reads 7 pounds, then I’ll hold the handle at the 12 inch mark and try to match the feel of that amount of force.

Now that’s it cool I have started using my heat setting. I remembered that there is no heat at idle. But usually the vents warm when I rev to 1500 and higher. I still hear the heater core gurgle. I have flushed the heater core, it’s not plugged. I think the air pockets from exh gas due to minor headgasket leak are interfering with coolant flow. But, I have driven it for 16 months with no overheating. And no coolant loss.
I did check coolant temp with scan tool this summer. Fans come on/off around 205f-220f.

Sounds like a small head gasket leak, like you said. Or possibly a really small coolant leak, if the level drops at all.