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yonkerse wrote:Does the temp go down after turning heat on high when driving it? I battled a similar situation with a 1990 Pontiac Sunbird and led to head gasket failure 40k later. Are head gaskets good?

I'm sure you have bled system and relieved any air pockets?

I think turning on the heat helps, but it still gets hot enough that he has to shut it down.

We did a compression test, head gaskets all held 135-150psi. We did not do a leak down test.

The system has been refilled and bled multiple times.

RJolly87 wrote:Why was all of the recent work done? Was it to try and fix this problem?

And did the issue suddenly appear, or it got worse and worse as it got warmer?

All the recent work was for the overheating problem.

It did not suddenly appear, just came on worse with the heat. We have been battling 90°F temps (record highs around this time of year).

RJolly87 wrote:And you did clean out between the condenser and radiator correct? Or at least look in there?

Yes this has been cleaned. It was pretty dirty so we were hoping that was it. You can now see light through the condensor and radiator, but still overheats.

00Beast wrote:Fans don't work, or they don't sufficiently cool it off?

Fans do work, but don't sufficiently cool it off.

yourgrandma wrote:Make sure the shroud for Tue radiator is intact. There's a duct that guides the air up from under the car. Without that it won't get any air at all.

The shroud is intact as far as I can see. Would you mind taking a few pics of yours Randy? from top and bottom?

Yeah, i can do that. Gimme a minute.

Someone mentioned combustion gas entering the coolant. Sometimes a head gasket will fail, and the coolant, and oil will not mix. Do you know anyone that has one of these kits to try?

http://www.tooltopia.com/uview-560000.a ... grabber_r1

harofreak00 wrote:

RJolly87 wrote:And you did clean out between the condenser and radiator correct? Or at least look in there?

Yes this has been cleaned. It was pretty dirty so we were hoping that was it. You can now see light through the condensor and radiator, but still overheat.

If it was dirty enough between them that you could not see through, maybe there is enough crap in there that it actually plugged between the fins of either and is blocking the flow of air.

Maybe pull the radiator and clean it or even have it boiled and then clean the fins of the AC condenser while it is out.

electric fans. The fan temp sensor. If the fans don't come on soon enough no amount of spinning will cool it off. See what temp the fans come on at.

Had this issue with a buddies porsche. new fan sensor and all fixed.

windshield_time wrote:electric fans. The fan temp sensor. If the fans don't come on soon enough no amount of spinning will cool it off. See what temp the fans come on at.

Had this issue with a buddies porsche. new fan sensor and all fixed.

Once you get past 35-40 mph the fans are pointless. The incoming air surpasses what the fan(s) will flow. He said it still does this when up to full speed. Which wasn't clearly defined, I thought highway speed was implied. Plus, he said the sensor was working correctly, and the fans are kicking on.

My dad came this weekend for Labor day and we took a look at the car today. It was only 70° outside today, so not too hot. We let it idle for 15-20 minutes and it never got above 200°. We took it out on the rode and it got up to 208° but did cool back down to 197°. We have confirmed its not a head gasket issue because it would have overheated today if it was. It seems to us that its just a poor cooling design. I ran it hard today it wouldn't overheat, but when it gets 90° it does. As long as it doesn't get super hot again this summer, it should be fine. I MIGHT install a bigger core radiator if it stays hot.

harofreak00 wrote:It seems to us that its just a poor cooling design.

I find that hard to believe, 90* may be hot for up there, but much of the US gets hotter than that, and I haven't heard anything about it.

Maybe compare radiators between what is in it, and the one for the shortstar? I wonder if the wrong one was put in maybe...

It is beginning to sound like a radiator problem. I recall years ago that Bill Bostick was working I think on an overheating problem. They had done what they thought was a thorough cleaning of the radiator fins. The radiator got accidentally knocked over after it was removed, and they were amazed at the amount of crud that fell out of it.

RJolly87 wrote:

harofreak00 wrote:It seems to us that its just a poor cooling design.

I find that hard to believe, 90* may be hot for up there, but much of the US gets hotter than that, and I haven't heard anything about it.

Maybe compare radiators between what is in it, and the one for the shortstar? I wonder if the wrong one was put in maybe...

I agree, if all intrigues had this problem I would be seeing them all over on then side of the road overheated. I almost suspect it is simply incorrect/cheaply made parts or something

Typically when we diagnose things, we test first by swapping known good parts and see if it works. What about swapping a known good radiator? Could jury-rig it temporarily.

Even if the radiator is swapped, there could be crap in the AC condenser blocking airflow. I think the radiator needs pulled and either replaced or thoroughly cleaned and a good scrubbing on the condenser.

A buddy of mine had an Intrigue, a little newer than this one, but sounds like a lot of the same symptoms, he replaced pretty much everything in the cooling system, until finally a shop did the water pump and the heater core and the car was fixed, never a problem since. He is convinced it was the heater core... He claimed it also had an audible popping noise from the cooling system, though I never verified this...

His was a 3.5, though...

I think there is an elephant in the room called the radiator.
The car is being described as having the classic symptoms of a partly clogged radiator.

Roger.

Another shot in the dark - I've also noticed in the past that one time getting hot can screw up the thermostat.
I had a brand new one on the ssei that wasn't regulating temp properly during idle, wasn't an issue until I installed the underdrive pulley and got the AC working again. I thought it was a coolant flow issue due to the underdrive pulley. But the thermostat wasn't opening more than 30% or so. That 'new' thermostat was actually bad off the shelf.

Quick check is to drop it in a large pan of boiling water. It should open 100% in a few seconds.

harofreak00 wrote: New radiator New thermostat (180°) New water pump New intake gaskets New UIM Fans are working properly No oil in coolant No coolant in oil No white smoke Coolant is boiling, but not over, no steam No air in system, has been burped properly You can feel the coolant running through the hoses when you squeeze them.

Has the lower radiator hose been replaced? Any possibility it's sucking shut due to separation?

Has radiator been flow tested?

I ordered a brand new radiator off ebay for $85 shipped. It showed up today so I swapped it out. The old one looked perfectly fine. It flowed exactly the same as the new one with a garden hose. I got the new one installed and it runs basically the same as before. It was only 75° today and the temps got up to 215° and then settled around 205°. I don't think its going to get warm enough anymore this season to properly test it. When I had the radiator out, I did notice that more of the condensor fins are bend than I would like to see. If I really wanted to keep digging into this, I'd probably replace the condensor. $75 shipped on ebay.

I went for the condenser just to ease my mind when I sell this car. When I got the old one out, I was pretty surprised how restrictive it was. About 50% of the fins are bent over. I can now see why the radiator wasn't getting proper airflow.

old


and new


Although its not going to get warm enough this season to fully test it, I did notice about a 20° drop in running temps. It hovers right around 180° right now, as before it was 205°. It was 70° during the test drive.

Wow, how does it get that bad? Did this thing take a hit in the front maybe?