Overheating
Asked by HoustonSam Dec 30, 2015 at 10:32 AM about the 2009 Chrysler PT Cruiser Wagon FWD
Question type: Maintenance & Repair
I'm helping my neighbor whose 2009 PT
Cruiser is intermittently overheating.
Radiator Fan (low speed was bad), 195
thermostat (bad), radiator (replaced by a
local shop) have already been addressed,
but it's still having issues.
I've purged all air from the cooling system
(even the heater core) and both fan relays
tested good with multimeter.
Neighbor replaced radiator cap.
Visually verified that there's no debris at all
obstructing radiator and there are no signs
to even remotely suggest that the head
gasket is a problem.
My only other thought is that the temp
sensor may be giving bad info to the
gauge.
Can someone please suggest where else
the problem may be??
Thanks, Sam
34 Answers
run a pressure test on the system, see if you have leaks , could also have air in the system , find the air bleeder or loosen the top hose until coolant comes out
HoustonSam answered 8 years ago
Rich, Thanks for the quick reply! There aren't any leaks and I've already bled all the air out of the system. (Got a lot out that was hiding in the heater core) Any other possibilities??
see if the upper and lower hoses both get hot and that the fans are blowing through the radiator , also pressure test the system see if you lose pressure. was the cap changed ? could be head gasket. but to be sure the pressure test will tell.
HoustonSam answered 8 years ago
The owner did replace the radiator cap I cannot be sure of the pressure rating of the one that he put on, so I'll spend the $20 and be sure that the correct one is in place. One of the few tools that I don't have is what I need to pressure test the system... Both the upper and lower rad hoses do get hot now. The upper wouldn't until I replaced the thermostat and purged the air from the system.
firebird338 answered 8 years ago
Is the vehicle actually over heating or just the gauge saying it's over heating ?
there is always buy and return at harbor freight.... see if the old cap helps
HoustonSam answered 8 years ago
Rich, I'll head over th O'Reilly. I've already got an account with them, so I'm sure they'll let me borrow one. Thanks for the reminder! While I'm there, I'll pick up the new cap.
firebird338 answered 8 years ago
Can you give us a little run down on how you bleed the system ?
HoustonSam answered 8 years ago
Firebird, Topped off system when cold, started car, let it get up to temp, verified new thermostat was opening, bled air from bleed valve by thermostat, turned on heater in car, bled more air from system until only coolant was coming from bleed valve, checked upper and lower rad hoses by feel and IR thermometer, monitored to verify electric fan was operating properly (at both levels because old fan was bad). Did I miss anything?
it seems like the system is open to air to me . has the car been sitting a while? does the overflow /reserve tank flood with fluid or bubbles?
firebird338 answered 8 years ago
Does the over flow tank have a cap on it where you can add anti freeze ?
HoustonSam answered 8 years ago
Rich, It's his daily driver so, no, it hasn't been sitting. He already had a local gas station/shop replace the radiator (ONLY the radiator. They didn't bother with the visibly bad thermostat) before I saw it. (One thing I cannot understand is that when they installed the new one, the locating pins on the top did not line up properly on the cross-member. The shop sheared off the pin on the passenger side and the drivers side is so off center that the bushing the is to keep it centered in the hole doesn't even set on it properly. My neighbor is retired and on a fixed income so I'm trying my best to avoid suggesting that he has, possibly, the wrong radiator.) When I first started on it, it was bubbling and overflowing from the reservoir quite profusely. After my work, it now doesn't overflow or bubble at all, but the dashboard temp gauge does intermittently indicate that it is well above the thermostat opening temp of 195 and the thermostat is brand new.
HoustonSam answered 8 years ago
Firebird, Yes it does. I'm going to my old-fashioned Prestone coolant tester to check the concentration. Could it possibly/probably be the coolant temp sensor?
if the gauge is going up and down , i would drive it around to see if she will level out, or show any signs of leakage , rev it while she is hot to see if the exhaust is blowing into the coolant . if that doesnt work and she is still running hot , it is possible that the radiator is too small for the engine.(if its not the correct unit).
firebird338 answered 8 years ago
Bleed air from system like this. Remove cap from over flow tank fill to full mark leave cap off start vehicle and let idle and reach operating temp coolent will start to fill over flow tank this is normal once thermostat starts to open coolent level will drop in tank add more coolent to full mark then put cap back on. That should completely remove air from system.
HoustonSam answered 8 years ago
Rich and Firebird, Thanks for the info. I'm going to give it a shot. I'll be sure to let y'all know what I find.
HoustonSam answered 8 years ago
Rich and Firebird, I just had my neighbor try to bring the revs up to 5000, but it would only make it to 3500. Pretty much sounded like it was hitting the chip, but it doesn't start red-lining until 6000. There were no signs of coolant from the tailpipe. Any ideas why he can't get the revs any higher? Could it be that the fuel filter needs to be changed as well?
firebird338 answered 8 years ago
Is the over heating problem taken care of and this is a new problem ? That would be the first thing I would try if fuel filter has not been changed in a while.
HoustonSam answered 8 years ago
The overheating is still intermittent, but the holiday and weather have put everything on pause. I was trying to get him to get the revs up to 5k and hold it there while I watched the exhaust for any signs of coolant, but he couldn't get it to go any higher than 3500. That's what brings me to suspecting the fuel filter. I tried to find the Wix P/N on their website, but there isn't one listed...
firebird338 answered 8 years ago
Also clean throttle with throttle body cleaner and add some seafoam fuel injector cleaner to gas tank. Also check air filter and replace if necessary.
HoustonSam answered 8 years ago
I've already replaced the air filter (it wasn't too bad, but it can't hurt) and he is now running through a full tank with the Chevron injector cleaner added. From what I'm finding on the web, it's showing that the filter is in the gas tank. Am I seeing that correctly???
HoustonSam answered 8 years ago
I was afraid of that... I'll make sure he runs most of the gas out before I start fighting with it again tomorrow. Really appreciate your help!!
HoustonSam answered 8 years ago
Firebird, Found coolant has contaminated the intake manifold at the #2 cylinder, so I'm guessing the head gasket is shot. What do you think and, if it is the head gasket, how difficult is it to do in a driveway??
firebird338 answered 8 years ago
Never did one on that vehicle before but it all depends on how much knowledge you no about mechanic work. The principal is the same on vehicles. I am going to suggest something you can try first it worked for me and still is working a year later add some Bars Cooling System Stop Leak for head gaskets. No guarantees but it is worth a try. If does not seal the first time do not continue to add more hoping it will work that is when you can clog up the cooling system.
i would think the car has a rev limiter , see if she will go past 3000 rpms when you are driving ..
Both the turbo and non-turbo have the rev limiter (around 4K) that limits the revs while at idle. There's nothing wrong with your car. There's also a limiter on top speed on both cars set by the computer. Around 105-110mph on the non-turbo, around 120-130mph on the turbos
HoustonSam answered 8 years ago
Rich, The 3500 limiter makes total sense, but the fact that his little PT Cruiser is speed-limited higher than my 2500HD (Stock chip= 99mph) is more than slightly disturbing...
HoustonSam answered 8 years ago
Firebird, I ended up tracking down a bottle of K&W Head and Block repair (I've always been a proponent of CRC products and FYI: CRC even steered me away from their fiber repair mix!). I am going to start on it once it warms up today.
firebird338 answered 8 years ago
Hey as long as it works I no the one I suggested is not the only one out there just let me know how it works so that I can suggest using that brand also.
I've always been partial to Blue Devil myself it worked on a old Honda Civic I had just do exactly what the directions say and it will work unless it is too far gone but as far as I know that old Honda is still running strong...lol