Overheating PT

[Ironman]

I had the same problem, with a few exceptions. first of all, I was losing coolant...out the overflow tank. The top would pop off and coolant would spill all over the engine. I replaced the thermostat, that didn't help the problem, so I took it to a shop and had them look over it, they did a pressure test and didn't find any loss of pressure, but they did notice that while the car was running the big black hose right under the intake plenum (I think that is the radiator return hose) got hard (it should be soft and "squishy"), meaning there was pressure buildup. They told me they had seen this before and that there was a hair line crack in the head gasket between one of the cylinders and a coolant port. this made sense to me because a hairline crack wouldn't show up in a 32 PSI pressure test, but with the compression from the engine. air would be able to get into the cooling system and cause the pressure. So they did a head job on it (I had them do all the belts, the water pump, and the power steering pump since it was making that whining noise) they also sent the head out to a machine shop where it was leveled (to get rid of the warp age that was present) so if there is coolant all over the top of your engine, and/or the hose feels hard, you might want to think of doing the head gasket.

[Deano]

All the radiator hoses feel fine to me. I've yet to try to work on it so far. That tends to keep the miles from piling up.

[dragonfly1021]

hi mine did is last year. I did all the you have done..mine was trash in radiator. I cracked the head on the compressor side. They took the radiator and flushed and fix the head. thank goodness it was under warranty. no problems since.

[Deano]

Called dealership to find out what they charge for any of the offending problems.

Could be thermostat: Labor- $140 Parts- $20
Could be water pump: Labor $650 Parts $100
Could be head gasket: Labor $1000 Parts $45

I knew the "could be-s" but didn't know the prices. Probably be better off not knowing. Hopefully, it's the thermostat. I should be able to do that myself. $9 thermostat plus coolant sounds a lot better than over $1000 any day.

[DarkLobo]

I wish I could read this post before monday...
On monday I got my first Pt Cruiser , 2003 , and today it overheats like it has the hell under the hood ...

it is absolutely normal unless... whenever I turn on the AC it goes overheating in less than 1 Minute and it dont stop even if I turn off the AC, had to stop the car and wait to engine cools .

I thought I had controled ... but today I was driving, you know testing it again , and I click the cruise control .... and again ... hot as hell ...
had to stop, luckily got help from highway support , and manage to got back home .

some additional details ... car stereo turns on and off on every bump of the road

so ... I have two theories ... electrical malfunction ... or .. extremely bad luck ....
Regards
Dark Lobo
P.S. I took yesterday to a mechanic ... they change the thermostat, put the fan in direct mode, check the radiator, and change radiator cap ... and no visible results ...

[CREWZIN]

DarkLobo,

Welcome to the forum. If you mean that they hot wired the fan so it's on ALL the time, they probably got the low speed part of the fan to work and that's what is ON all the time. When the A/C is on, and you come to a stop and everything starts to heat up, the high speed part of the fan needs to come on to keep it cool. You aren't getting that high speed it it's hard wired. Someone else on this forum had the same thing done to his cruiser by a mechanic that's not familiar with the PT.

On the first part of your question you said once it started to overheat you turned off the A/C but it didn't help. Because the high speed fan wasn't coming on, once you start to overheat there's nothing you can do but either stop the car or get on a highway ASAP, up to speed (55+) without coming to a stop and let the cool air coming thru the radiator cool it down. You don't want to do this if the temp guage has already hit the red line. You might not make it to the highway without blowing a gasket or warping the head.

Although I've pointed to the fan as your problem, there are relays in the fuse box in the engine compartment that could also be bad and lastly, the computer turns the fan to high speed through engine temperature sensors so the sensor or computer could have a fault. Most likly though, it's the high speed part of the fan.

Does the fan come on in the morning when you first start the PT and you have the A/C on? It should and that's the low speed. As I said the high speed doesn't come on till you reach a pre-set temperature.

[DarkLobo]

Hi Crewzin
thank you for the quick reply
Maybe I wasnt enough explanatory, but I was a little hot minded also, I was planning a trip to my hometown (about 400 miles from where I am ) and couldnt get even 30 miles in the highway before the engine gots hot...

As I stated before, I bought the car on monday , used car , but in all the tests I made never overheated , actually, in tests I didnt used the AC, and most unfortunatelly, didnt take an expert with me to check the car first ... you know I was in love with the car ... and people do crazy things when in love ...

So, the car started overheating almost the third day after buying, and using in heavy traffic .

on thursday I take to a mechanic just for a tune up , and asked to take a look on the overheating problem (I know that it should be taken to an electrical , and radiator expert, but the mechanic never had troubles in the past with my previous car ) they made the tune up , and take a peek on the car ... dissasembly the radiator and took to a radiator expert to check for dust, and everything was ok , change the radiator cap, just in case , and set the thermostat in open mode (I dont know exactly what they did, just charged me 40 bucks for doing it ) and take the car to an electrical expert, and found no problems with the fan ... but just in case hotwired the fan , so it was always working ... and as an observation, they told me , the fan was already in high speed mode.
they tested the car for 2 hours , but no turning the AC ... so it NEVER overheated ....

I picked up, and made some tests .. .and voila ... without turning on AC I can drive all I want , and everything is ok

I got home, and 3 blocks before getting home , turned on AC and it overheated in less than 2 blocks ...

So I thought.. I have all figured out ... so lets drive and dont use the AC
but when I was hitting the road , and as I told you 20/30 miles in the highway I started messing with the cruise control... just for testing it ... and the moment I touched it ... Overheating all over again in less than a mile (I was in 60/70 mph) so I pull over

Open the hood ... and fan was working ... but coolant was boiling

wait for an hour and run again ... and overheating in less than a mile again
pull over again ...

a guy from tourist highway services (mexican car support in the road ... also called green angels ) offer me to push my car back to the city ...

but instead I asked him to just escorted me ... (because temp was medium at the moment ..)
then we pull over in a better spot , open the hood ... he opens the tip of my radiator cap (a little red lever to release pressure .. ) but insted of releasing hot air .... it sucked air ... and the exhaust thing boiled faster ... in the end when enough pressure was released , I turned on the car , he fully open the cap , and started pouring water ... until the radiator was cool ..
I got back home ...
temp as normal ... 3 or four blocks before getting there ... I started messing with everything ... AC , cruise control... and again ... Overheating all over again ...

so thats my story ... many things pending to do ....
first take to an AC expert to check for pressure, and R134 or whatever is called...
then to a Electrical Expert to check for every single amp, and volt in every wire , and in every situation ...
then ... pray .... a lot of praying ...
then ... I dont know what else to do ...
the car is in excelent conditions... just ... overheats ...
and the stereo turns on and off in every bump of the ride ...

Dark Lobo ... from Reynosa Mexico ...

[CREWZIN]

Dark Lobo,

First; unless something is terribly wired wrong, all my home-schooled knowledge says that your Cruise Control had nothing whatsoever to do with your overheating. Forget that part of it, it was about to overheat anyway and using the CC was just a coincidence at the same time.

After all that you said, my guess it that your problem might be water related. A bad head gasket would make it overheat all the time.
Are you loosing any anti-freeze on your PT? Are you using a 50/50 mixture of anti-freeze and not just plain water? Is the cooling system being bled of any air trapped inside?

Also, your explanation of your radiator cap sounds like it's an after market type. Make sure it's rated for the correct pressure for the PT.

Your mechanic hot wired the fan on high speed and took out your thermostat (set it to open mode). I'd find a new mechanic. Both procedures are a slap hazard way of fixing things.

Last but not least, your radio has a bad ground or broken solder joint somewhere inside. Can't help you there.

ANY OF YOU CERTIFIED GUYS READING THIS THREAD HAVE ANY OTHER IDEAS ON THE OVERHEATING PROBLEM ??

[DarkLobo]

Thank you very much again .
Of course I will change the mechanic, and on monday replace the thermostat for a new one.
Im thinking now going to the official chrysler dealer they have mechanical service , even it is as expensive as an eye of the face. and thats only for diagnosis ...

I use coolant mix 50 /50 , no leaks observed on the oil measure thing ...

not being a mechanical myself, my guess is that water pump stops working for some reason (most likely electrical reasons ) whenever AC is started , because I checked and the fan is working all the time

Best Regards, and thanks for your help
Dark Lobo

[CREWZIN]

I'm almost positive the water pump is mechanical so when it fails it fails and either leaks a lot from the front or doesn't let the coolant run around the engine to cool things off so you wouldn't have the times you say it doesn't overheat without the A/C on. It would overheat all the time.

Good luck at the dealer. Make sure yo have them run the engine with the A/C ON to see it overheat. Please come back and let us know if/when they find the problem.