Heating AC and Engine Cooling

There is a relay for the cooling fan located under the air cleaner box. Actually there are two. One is called the fan relay, the other is the high speed fan relay. One of those relays might be stuck on all the time. Otherwise you may have a failed or unplugged ECT sensor, or an open circuit between there and the PCM, which could make the PCM think the engine is running hot, even when it is cold. Of course, the PCM may have failed or someone could have straight wired the fan.

Go to the parts store and get a cheap gauge to check the level, your system may have a slow leak that SHOULD have been caught if it was charged by pros. If not buy a can of leak sealer and add it to your system, this will also probably top off your system and get you back in business, if not add another can, IT'S EASY AS HELL REALLY!!

first look for a label or sticker on the cross member above the radiator or on the compressor that indicates the amount of charge and refrigerant type (r-12 or r-134a). it's quite possible that the car was manufactured using r-12 and was retrofitted for r-134a since r-12 is no longer available. in any event, look at the schrader valve in the line near the compressor. it looks something like a tire valve and may have a cap on it and will be on the larger of the two lines going to the compressor. if it is the same size as a tire valve it is r-12, if it is larger it is r-134a. in any event if you need to add freon you will have to convert to r-134a since r-12 is no longer available. you can do this yourself with conversion kits available at any auto parts store. be sure to follow the directions. you don,t necessarily have to pump down the system doing it yourself but be sure to change the accumulator and oriface tube. most of the old oil is in the accumulator and this gets rid of it. the new oil for r-134a is different and will not mix with the old oil. make sure the retrofit kit comes with oil. if you can't get to the oriface tube leave the old one in at somewhat reduced efficiency. the whole job should be well under $100. alternately you can have it done by a mechanic but he will have to find out where the old freon went and look for a leak. hope this helps.

There seems to be difficulty in finding a clear cut answer to this problem, which affects more PT Cruiser owners as their vehicle ages. Many owners have spent countless dollars and hours having thermostat gauges, radiator fans, radiator caps and water pumps replaced without the problem of overheating being corrected. While any of those parts can go bad, be sure to be upfront with your dealer to provide evidence that their diagnosis is correct and an agreement in writing to protect you in the event they are wrong.

Your first step with the dealer is the request they have checked your coolant for combustion fumes/chemicals mixed in it. They may have to order a kit, this should be done at their expense not yours. If the test comes back positive (ask for the results) stop working with them at that point. Your cause is with the head gasket, and any other recommended repairs to your car without correcting that will be a waste of money.

If this comes back negative, the second thing to check is to be certain they properly checked the fan including the fan motor. There are numerous reports online suggesting the high and low contacts wear out, which can effect the fan running properly and thermostat opening correctly. Be direct with the dealership, and verify that this is not the cause alone before they sell you an entire new fan assembly (which can cost 3 times as much as the motor.) The dealer may test the fan by actuating it, and report it runs fine. Be more demanding than that. If it is the fan call around for best pricing, but look to spend between $350 and $650 for parts and labor on a new fan.

If the fan is not your cause, your next source would be the thermostat. It is recommended that prior to this however that you have your radiator properly flushed to be certain your overheating isn't caused by poor circulation through your cooling system. It's better to pay for this first and find out it's not your problem then to pay for a new and more expensive thermostat only to find you could have flushed it. Call around for exact pricing, but look at $300 - $400 for parts and labor on a new thermostat.

Finally if none of the above seems to have lead you to the proper place, it may then be your water pump. The cost of accessing and replacing this is nearly as high as the head gasket as a teardown of the engine is needed to investigate further. This can cost you between $700 and $900 at a dealership, not including labor and parts to actually repair the problem. Call around to various dealerships for the best price if you decide to tackle a head gasket or water pump.

With any of the above steps, make sure a pressure test is done of your system. If one is done and a pressure leak is found great, but don't let your dealer off the hook by assuming the first problem they find is the only cause. Make sure they have diagnosed your problem by investigating all options! Many PT Cruiser owners have made multiple trips to dealers by letting them! Let their frustration save you money down the road.

classic symptoms of a blown head gasket.... have someone crank engine while you look at fluid with radiator cap off..see if bubbles come out ,that indicates combustion gases escaping into cooling system. also, see you tube video about combustion leak detector...you put blue dye in radiator, you pump syringe device ,to circulate dye....if blue dye turns yellow, you have blown head gasket....you can buy a combustion leak detector on internet for about 30.00 including shipping ,dye and everything.

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One that doesn't run, and whose Number 1 Main bearing journal isn't trashed.

Or, more specifically, one that doesn't run, has a good Number 1 Main bearing journal, and also has dual pressure relief valves in the case.

The temperature door actuator controls the opening to the heater core. The heater core door regulates the desired temperature in the passenger cabin.

Mine isn't but if yours is, you may have bad coolant, a bad thermostat, a bad water pump. There are several things that can cause over heating.

When my head gasket went as i was driving i lost alot of power as one of my cylinders had been taken out along with a valve. Beause of the heat it also warped the cylinder head which meant it have to be skimmed. This could be the case with your

Replacing the gasket is actually quite simple and shouldn't cost much. The problem is figuring out how much OTHER stuff has to be removed to get to it. Most shops have a book that lists the amount of time required for each task based on an experienced mechanic performing the job in a timed environment. Even though it's simple to replace the gasket, shops will definitely charge more if they have to remove a lot of peripheral stuff to get to it. answer that depends on what engine you are working on i would rather replace a v8 inlet than a 4 or a six v8 is on top and not much to remove, 4 and six are on sides along with exhaust mannifold and usually lots of other junk

After a little research I found out that the registers for all the vents are opened by vacuum hoses. After checking all the vacum hoses I could find, one hose in engine bay had been severed when a new battery was installed and pinched the hose between the battery and the battery tray...one small piece of hose later, and all is working great.

1. Low or no freon 2. ac clutch not operating 3. other ac problems; wiring ect

In order of probablility: low coolant level, faulty thermostat, plugged radiator, damaged water pump, collapsing radiator hose.

The pressure will rise and the oil can thin.The purpose of the out door section of a residential a/c system is to condense gas into a liquid my means of cooling the gas.

It take a pulsed signal from the ECU via the purple wire, starts the fan and controls its speed.

Find the highest heater hose joint on the dash under the hood, turn the heater water control on, run the car so the water is circulating and loosen the clamp and loosen the joint at the hose to let the air out. When only coolant flows tighten the connection and your done.

911 3.2 Carrera (1984

There is a big difference. Stock radiators are sometimes just barely adequite, and it is not unheard of for them to vary the installed one depending on the region that it is going to be shipped to. You can purchase an aftermarket or rebuilt radiator with additional cores for better cooling. Remember to use the fan shroud as it is the only thing forcing the fan to pull air through the radiator.

Internal combustion engines are cooled by anti-freeze (AKA coolant). The anti-freez circulates the coolant through the engine and radiator. When the cooland flows through the radiator, the air passing though the radiator cools the anti-freeze, hence allowing cool anti-freeze to ciculate through engine, thus reducing temperature.

It is located behind the glove box, or lower dashboard storage area. You have to disconnect the air piston on the right side and lower the box. Then remove the filter box(just slides out). Do not throw out the frame, you will need it.

there are two air lock 'bleed' taps, one down on the junction of the pipe work on the front right hand end of the engine, it has a small square headed bolt, the other high on the rubber tubes feeding the heater, its plastic and unscrewed by hand.

best way, slightly release one at a time until fluid leaks, tighten, run engine, repeat until no air comes out, can take a while and the last bit might take a long drive to shift,

BTW this engine can be prone to cooling system clogging, so that some air remains, its very important to clear it as the engine isn't cooled well in this case, and can be damaged, some of the tiny return tubes, specifically there to bleed air automatically, can clog with emulsion, after many years not being maintained, so it might be an idea to check these are clear by removing and pushing a wire through, consult an expert about this if you're not sure.

9 to 13 PSI.

diagram showing where the thermostat is located

the fuel filter is located on the drivers side just in front of the tank. brewski