PT Cruiser 2001 overheated?

Neighbor’s car (mileage unknown) had sat for a few weeks; battery too far down to start. Charged battery (took a few iterations), then let car idle to “finish charging the battery” (or whatever). (Have sympathy, people; neighbor can’t drive right now b/c of medical problems. That’s why the car sat.)

After 30 (or 60?) minutes “smoke” started coming out of engine area. Shut off engine. Art came home and was asked for help/advice.

“Smoke” was more likely steam. It stopped after a few minutes. Watery looking fluid on driveway; neighbor’s housemate says reddish, but I could not see that. I restarted the engine briefly to check temperature gauge. Way high. I suspect “boiled over from excessive idling” (but maybe it should be able to idle that long, and there is an underlying problem). Coolant refill bottle has some fluid in it, but not nearly up to the “Full Hot” mark.

My plan: Wait an hour for engine to cool down. Take off radiator cap to see if coolant is low there. If yes, refill with plain water to see if system operates normally; add water also to refill bottle. If system seems normal, drain the water and replace with proper coolant mixture. If none of that helps, tow it to a mechanic.

Questions: 1) Does overheat after 30-60 minute of idling indicate underlying problem? 2) Any comments on my approach? 3) What is procedure if we do have to refill radiator? Do I have to let water pump run to move water into voids? Do we need to burp the system? How?

Man, is that engine compartment crowded.


Wait longer than an hour. You don’t know how hot it got, and it takes awhile to cool down to safe temperatures. If you feel the top of the radiator and it’s more than “warm,” don’t open it.

Figure out what’s leaking first and fix that. Fill it with distilled water to begin with to trace the leak if you don’t already know where it is (don’t do this if it’s still below freezing where you are – or at least, don’t do it and then let it sit overnight). Before that, look around all the hoses and the radiator for signs of a leak - often a white powdery-looking streak.

[quote]Do I have to let water pump run to move water into voids? Do we need to burp the system? How?

With a cold engine, fill the radiator. Leave the cap off. Start the engine, wait till it starts circulating, then watch the level - as it drops, put more in. Sometimes it’s helpful to squeeze the upper radiator hose to force any air bubbles trapped there to move. There will also be a banjo bolt at the top of the system, whereever that is in your car. Crack it open to bleed air out through there - you’ll know you’re done when a steady stream of coolant comes out.

BTW it’s possible that the cooling fans are not working, which would cause it to overheat at idle since there’s no airflow over the radiator. As it overheats, it could force coolant out past the radiator cap. So be sure the fans are working, and consider replacing the radiator cap.

@art1966 This might be one of those times when helping someone might not be the best move. I myself would just say have a shop solve this so they can’t claim I did something wrong.

I’d say distilled water is not needed. Chances are once diagnosis is done, it will need a refill of the correct mixture. And catch any spilled water-coolant (poisonous to animals and people) and dispose of it properly.

Also set the heater to Hot. The fan doesn’t need to be on. In case there’s a valve between engine and heater core, that will open it and let the whole system get burped.

Thing is, we have no idea what the tap water has in it where OP lives. If it’s particularly hard like it is where I live, you can get mineral buildup. So out of an overabundance of caution I recommended distilled.


Took off radiator cap. No coolant visible inside (tube runs vertically down side of radiator). Added water to overflow bottle and to radiator (did not take much). Started engine. Radiator level went down a tiny bit; added a little more water. After several minutes, level not dropping any more. Squeezed upper hose; water blurped out of the radiator opening. Checked temperature gauge; still stone cold (but that could be from no coolant at sensor). Peered into radiator opening again; still brim full. A few teeny tiny bubbles coming up. A couple of more minutes and the bubbles got a little bigger and steadier, and something murky began rising in the water there.

I shut off the engine and advised the neighbor to get professional service. I mentioned that bubbles MIGHT indicated head gasket problem. Fortunately, neighbor has fancy warranty from dealer, that includes towing.

Neighbor (good neighbor!) will keep me informed, and I’ll inform Car Talk if anything interesting happens.

Thanks for the advice.

There is usually air trapped behind the thermostat after refilling the cooling system so you will see air escaping until the engine reaches operating temperature. It is unlikely that this overheating event damaged the head gasket or cylinder head.

The reason the engine overheated might be that the radiator fan isn’t working, whatever the cause it will need to be towed. I wonder what sort of dealer offers a warranty on a 17 year old car?

Idling an engine for long periods of time is not the preferred method of recharging a battery, let them use your battery charger.

Holy Big Dollars, Batman.

Something murky coming up - you picked a good time back away from this project. Good luck to you and your good neighbor. It will be interesting to hear from you again and get the rest of the story.

Neighbor got the car back a few days ago, but this is the first chance we’ve had to communicate about it. Here’s the e-mail I received:

“Greetings, Art! To let you and the the ‘car guys’ know…I really blew it letting the car run that day! When all was said and done, the radiator, hoses, and fans had to be replaced…needless to say, it cost a chunk of change (gulp). I keep saying no more big expenses for my 17-year-old girl, but I fear this was it.”

Myself, I’m a little suspicious of replacing the fans; but could be. Radiator and hoses might have been ready for replacement even without the long-term idling.

Thanks for the advice, “car guys”.

(BTW, when neighbor mentioned the warranty back when I started this thread, I think the term used was “lifetime”. Still big $$, I’m sure, but neighbor may have gotten value in peace of mind – if not in towing :grin:)

The coolant fan temp switch failed on my Corolla couple of years ago, and the result was it overheated during a long idling session waiting in traffic, and popped the radiator. I had to replace the radiator, coolant, and the fan switch. So tell your neighbor they aren’t alone … lol …

The lifetime powertrain warranty was offered on certain new vehicles at no addition cost from 2007 to 2009 but that won’t cover the radiator, hoses or cooling fan. Are you sure it is 2001 model year?