How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask sprinkles08 Your Own Question
sprinkles08, ASE Certified Technician
Category: Chrysler
Satisfied Customers: 23004
Experience:  ASE Master & Advanced level certified, Chrysler Master Certified, Trans and Hybrid Specialist
Type Your Chrysler Question Here...
sprinkles08 is online now
A new question is answered every 9 seconds

1997 Chrysler Concorde: overheating problems with a mix..temps..drives

Customer Question

1997 Chrysler Concorde 3.5L. The car had overheating problems with a mix of 50/50 (remembering that we live in 100+F temps during the summer) in short drives, and with the A/C on. Due to issues with attempting to get the issue fixed and said mechanic doing the job improperly, another motor was dropped in, same 3.5L engine. The same problem ensued. Overheating with boilover. Fluid would be replaced, and then bled to remove any air pockets. The problem ensued. The fan assembly has been replaced. The thermostat has been replaced. The water pump has been replaced. The cap has been replaced. All hoses are good. The only thing that has not been done is the radiator flushed or replaced.   There are no error codes (the last time I checked) coming off the vehicle. I'm open to any and all suggestions other than getting another car.
Submitted: 8 years ago.
Category: Chrysler
Expert:  gentry314 replied 8 years ago.
do you have flow in the radiator and is the cooling fans kicking on is it bubb;ing through reservoir
Customer: replied 8 years ago.
Yes, there is flow in the radiator and the cooling fan is kicking on. No, there are no air bubbles in the reservoir, as the system is bled via the valve after replacing coolant to remove the air pockets.
Expert:  gentry314 replied 8 years ago.
i had a concord due that and what i did is while the engine was running loosen bolts on t-stat housing and snugged back down took remaing airout of system car did not over heat anymore
Customer: replied 8 years ago.
The thermostat has been replaced twice, and currently is not even in the vehicle.
Expert:  gentry314 replied 8 years ago.
if everthing in the cooling system is funtioning correctly must be an issue with engine
Customer: replied 8 years ago.
The engine has been replaced.
Customer: replied 8 years ago.
To help everyone here is the deal. The vehicle overheats during hot weather with short trips (we live in 100F+ temps) with boilover, we can not run the A/C. Fluid is replaced, and the coolant line is bled to remove all air pockets. The problem continues. The following has been replaced and the vehicle still overheats.

1. The ENTIRE3.5L engine has been replaced (the engine came from another 97 Concorde that had a rear impact and junked. The 3.5L engine had only 64,000 miles on it), THEN following that:
2. The thermostat, TWICE replaced, and now is not even in the vehicle;
3. The fan, which comes on when the temp reaches a hair above half;
4. The water pump, which was replaced because it leaked and corroded
5. The cap, actually twice replace with two different brands
6. All hoses

Points to note. The check engine light does not come on, EVER for this issue. There are no codes coming out of the ECM, other than the start code and end code.

I am seeking an answer as to why the car continues to overheat considering that nearly everything regarding the cooling system has been replaced. We run a 50/50 mix but are going to start using WaterWetter as a bandaid until the problem is solved. The thing to remember with troubleshooting this car is what could cause overheating that is still original to the car, that has not been replaced. Is there a switch that we are missing? Is there a relay that could be bad? The only thing that has not been done for this issue, is flushing the radiator however, in temps below 90F, there is not an overheating problem however, we still can not run the A/C.
Expert:  saabspecialist replied 8 years ago.
Radiator could be mostly plugged and still have some flow through it.Especially if at one time some "stop leak" type stuff was ever added to it.Seems to me like a radiator is about all thats left.
Good Luck
Customer: replied 8 years ago.

As far as we know, no stop leak has ever been added to the vehicle, at least since we have had it. The previous owner kept every record for this vehicle, up to and including tire rotations/changes and oil changes and was a car owner that did things by the book and only through the dealer garage. The previous owner had replaced the original radiator about 1 year before we bought it. I think they may have had issues with the vehicle overheating also.


I've read something about the catalytic converter possibly being bad, causing excessive back pressure that could increase the temp of the engine however, seems this would happen all the time, and not just in hot weather. However, this car is tested every year for emissions, and passes, so it's probably not that.


I think we are going to have the flusing done in the next few days, as it is the last "hardware" item (Im a computer geek) that needs to be addressed. If it continues, then it has to be a sensor, a relay or a switch is not working correctly, thus something hardware wise isn't working the way its suppose to. And it would seem the check engine light would come on and I know it does work, because the check engine light never comes on with this. (And the check engine light does work, as the timing belt broke on the "new" engine because of the water pump leaking, which was a new timing belt when the engine was dropped in. And it certainly came on then!)


I'll let ya know. Thanks.

Expert:  sprinkles08 replied 8 years ago.
Hello and welcome to JustAnswer!

This is a new expert. I'm sorry noone has responded to your last reply.

I really think you have a radiator issue. Everything else has been covered. The water pump and thermostat have been replaced, the system has been bled, and the fan works. The only thing left is the radiator's ability to remove heat from the coolant.

Over time the entrances to the cores in the radiator will start to get built up with corrosion close off. These cores will stop flowing coolant and the others still will. You will still have flow through the radiator, but not the whole radiator will be working. You can see this with an infrared thermometer while the engine is warm, there will be spots in the radiator that are cooler than the rest.

Flushing the radiator in this condition rarely will fix the problem. When it's flushed the liquid will flow through the cores that still flow and not touch the ones that are blocked, like electricity the water will take the path of least resistance. I would recommend replacing the radiator at this point. It's cheap anyway, you can get an aftermarket one for little more than a hundred bucks.
Customer: replied 8 years ago.

My other half has one question about this. He wants to take the lower hose off to see if there is sediment accumulated there, and at the exit of the radiator. Would this be a good sign of the problem you state?


But could I ask one additional question. Why isn't the check engine light or temperature light coming on when this happens? (Just trying to cover all bases.)

Expert:  sprinkles08 replied 8 years ago.

You possibly may see something if you take off the hose but I won't promise it. It depends on how much buildup there is. The small diameter of the radiator hose won't give you very much of a look at the part that matters, the inlets to the cores running up and down the very left side of the radiator.


The check engine light will never come on for an overheating problem. It will come on for things that cause the tailpipe emissions to exceed 1.5 times the amount the amount the car certified for basically, or OBDI things like opens and shorts in electrical components. The overheat light will eventually come on when the engine overheats but you may not be getting hot enough to see if. The temperature light will come on at something like 260 degrees.

sprinkles08, ASE Certified Technician
Category: Chrysler
Satisfied Customers: 23004
Experience: ASE Master & Advanced level certified, Chrysler Master Certified, Trans and Hybrid Specialist
sprinkles08 and 6 other Chrysler Specialists are ready to help you
Customer: replied 8 years ago.

The other half says, "sounds good to me"! And he says thanks!

Expert:  sprinkles08 replied 8 years ago.

You're welcome, and good luck with your car!


Customer: replied 8 years ago.

It makes sense. The previous owner replaced the radiator. If there was gunk in the radiator/engine, and it was a severe enough problem, gunk probably got into the block. Replacing the radiator only "bandaided" the issue at the time, and since the radiator could flow again, the problem was temporarily fixed.


However, there was crud still in the block. So over time, as the radiator began to build up gunk again, and with the gunk in the block possibly migrating through the system, the original problem surfaced again, this time with us.


Replacing the engine (this was due to work on the engine to correct damage done by the overheating, in other words replacing the seal and correct a small warp issue, and they put in the crankshaft crooked and then it breaking) only fixed "part" of the problem again, as the problem with the system that acutally cools the water (the radiator) still existed.


This also combined with the fact that the water pump leaked (as was so corroded and ended up corroding the timing belt so bad that it actually rotted a new timing belt when the motor was replaced within a three month time period)and gunk was found in it, reinforces the fact that there is gunk in the system.


Other half is gonna take a look at the bottom of the rad (if there is that much gunk in the system, then there should be some signs of it there as there were signs of sediment in the overflow tank) and I think we are gonna get an aftermarket one. Comparing the price for a rad flush ($70) vs the price of an aftermarket rad ($100-$125 and pretty easily put in ourselves) its gonna be a new radiator.


Unfortunately since he's a truck driver, its gonna be at least a week before he's back home! Will let ya know when we get this done.


Lets hope this is the end of this issue. The car is a good car. It might be older, but you can't beat the fact that its paid for and insurance is low on it! And the fact, who wants to steal an older car, in a town that has high auto theft!


Again thanks for the info.

Expert:  sprinkles08 replied 8 years ago.

I agree with the price of a new radiator vs. a flush it makes since to replace it, especially when you'll never get everything out of it with a flush.


And yes, you can't beat the insurance rates on these old cars, or the great fuel mileage. Mine 94 has 238,000 miles on it and running strong!