Well guys, its at the dealer to be diagnosed

You may have read my posts from the past couple of weeks about my 2000 3.5L overheating. Well, after an exhaustive efort or doing everything I know to, I just give in and took it to the dealer hoping that someone there would have seen this problem before. Its obvousily a fairly common problem because I have seen numerous posts on here and other boards with folks experiencing the overheating to the point of a popping sound coming from the engine. Problem is, no one returns to say how they fixed it. They either overheat the engine totally to where they blow the head gasket or they must get rid of the car.

Oh well, just waiting for the call from the dealer. They have already called once and said they cannot get it to overheat. Doesn't suprise me, because it come and goes but recently it has been doing it much more often. I'm guessing they did not drive it long enough this morning. Its very cold here at the moment. It will be interesting to see what they say. I will post an update ASAP for those that still have this problem, or will have it in the future.

Well, here is the update. The dealer mechanic called me personally and said he drove it 20 miles both highway and around town and let it idle in the shop. It never once overheated. I just laughed. He ran all kinds of tests and said there were no codes showing, all the sensors and gauges work, the water pump is fine, and there is no sign of a blown head gasket.

I picked it up yesterday and drove it thinking it would overheat for sure once I got in it. I even let it sit and idle and it never overheated. WHAT THE HECK IS GOING ON??

Like I said, I had to stop three times on the way to the dealer that morning to let it cool down.

I drove it for a little while this morning and it ran fine. What in the world has had it overheating for the past month or so? Anyway, I guess I will keep driving it until it overheats again. Everytime a repair place drives it, it runs normal. Only think left to replace would be the radiator and water pump.

I WILL figure this out.

Well, here is the update. The dealer mechanic called me personally and said he drove it 20 miles both highway and around town and let it idle in the shop. It never once overheated. I just laughed. He ran all kinds of tests and said there were no codes showing, all the sensors and gauges work, the water pump is fine, and there is no sign of a blown head gasket.

I picked it up yesterday and drove it thinking it would overheat for sure once I got in it. I even let it sit and idle and it never overheated. WHAT THE HECK IS GOING ON??

Like I said, I had to stop three times on the way to the dealer that morning to let it cool down.

I drove it for a little while this morning and it ran fine. What in the world has had it overheating for the past month or so? Anyway, I guess I will keep driving it until it overheats again. Everytime a repair place drives it, it runs normal. Only think left to replace would be the radiator and water pump.

I WILL figure this out.

Good Luck! Might have something to do with the radiator fans not turning on.??

Based on your other posts about this problem it is odd that the lower hose was cool (if not cold) as you indicate. I hate for you to waste coolant and money to pull that hose, but it's almost as if there was a plug before or in the hose itself. I don't know what it could possibly be as the hose is fairly sizeable in diameter.

It's frustrating throwing money at parts when you nor the paid mechanics have a good idea as to what it going on.

I would replace the water pump before the replacing radiator.

When it's warm enough for the AC compressor to kick in, turn it on and see if both fans (radiator and condenser) are working.

I don't think it matters (new or old style) regarding your post about replacing the thermostat. I would think it being brand new is fine.

A bad temperature sensor is a good possibility as someone mentioned.

Another far off idea is that maybe the tension on the serpentine belt is not quite right causing the water pump not to be turning optimally. The tensioner is automatic unless it wasn't bolted down tight enough and you are getting too much slack in the belt. Just an idea.

Let us know!

Just another update to the overheating issue. Since the day I took it to the dealer to be looked at, it has yet to overheat again. Its running just a smooth as it can run.

I have no idea what was causing it to overheat all the time.

To answer some of the suggestions, both fans run and gauge and sensors checked out fine at the dealer. I doubt the water pump had anything to do with it because it would still be doing it in my opinion if that was the cause.

Oh well, if it starts doing it again, it will go back to the dealer.

for some bizarre reason (some) 3.5L Intrigues act bizarre in the cold. Maybe you will need to put this car away for a month when it acts up again due to the cold weather. It's below freezing weather where I am and my 3.5L Intrigue is an absolute champ = never had an overheating problem and changing the coolant to universal actually brought the temp down a click or two (1 click = width of the coolant indicator needle)

You would think more Canadian 3.5L Intrigues would be having more problems = maybe they have different programming etc. than the U.S. ones.

The tranny is also cooled by the radiator in the Intrigue. If your tranny is not cooling well (bad tranny pump etc) it will also heat up the coolant. (doubtful in your case)

http://www.carforums.net/showthread.php?t=39764&page=1 (insight about Intrigue overheating)
-temps go down with the heater off.

http://www.automotiveforums.com/vbulletin/t322107.html (overheating due to engine coolant passages being clogged)
-there should be places that can power flush your engine coolant -and ask them to do it 2-3x normal
-DexCool when in contact with Oxygen breaks down very quickly (must change out radiator fluid if working on car)
-DexCool is incompatible with other coolants
-change out the DexCool and go universal since the last Intrigue was built in 2002 (5years ago)

Has the water pump been changed yet? I have seen cases where the pump impeller has become loose on the shaft and didn't pump water efficiently at low RPM. I have also seen impellers literally eaten away by old coolant. It could also be partially clogged radiator passages. I'd pull the thermostat and verify good coolant flow. -the car will cool down better if driven at high RPMs = bad coolant pump.

a4x4toyota's previous thread about this issue:
http://www.automotiveforums.com/vbulletin/showthread.php?t=670089

I believe your coolant pump impeller blades are bad due to old DexCool eating them. Try manually shifting your car and keeping the Revs up at 3k RPM etc. You could even do this test in while in Park (safer) I also think your engine coolant passages are clogged with crap = I would purposely rev the car up to higher RPM (watch the heat) and see if you can force some of this junk out (I would be nice to have a coolant filter built-in to the system -maybe these aluminum engines need a coolant filter)

-maybe make some sort of sediment bowl type of filter (old crap never goes out of style)
http://www.mako.com.au/auto/tefba.htm

http://www.mako.com.au/auto/images/body.gif (I believe you could easily make your own with an old oil filter) -get those revs up and filter out the coolant, maybe there is a coolant cleaner.

http://www.caswellplating.com/permatex/images/perm80030.jpg