2004 Chrysler PT Cruiser • 4 cylinder 2WD • 110,000 miles

I have 2004 pt cruiser gt turbo 2.4L
Hi everybody sorry for the long description here, I am not mechanic, I could do some minor repairs, I had changed starter once and alternator that’s all. I appreciate your input on this issue below.
The car stalls after driving 20 minutes and just a few seconds before that, the check engine will come on. In the beginning when this stalling problem started the car wouldn’t start after stalling and I had to wait about an hour until it starts. I took the car to a mechanic he connected the car to a computer to check the codes. He got 2 o2 sensors and tune up and speed idle control sensor. So he changed the 2 O2 sensors, speed idle control sensor, spark plugs, wires and air filter. I told him to reset the check engine light and the codes but he said it will reset by itself, so he didn’t reset it. After 20 min drive I had the same problem.
I checked on the receipt for the parts there was no speed idle control on the list but it was Selenoid linear IACV (I wonder if this is the Idle speed control sensor?)
Then I took back to the mechanic he checked the codes again and he said he is getting the same codes and he didn’t know why. That was it with him. ($700 cost)
I took the car in another day to another mechanic he said to leave the car and he will check the car with bunch of test machines hooked up to the engine and drive with it so he can see what is happening when the car stalls. Unfortunately (according to him) he drove the car for a while and nothing happened but he cleared the codes and the check engine was gone.($60 cost)
So I picked up the car and after 20 minutes the car stalled. The garage was already closed. I went the next day and he wasn’t there. I said the hell with him.
I took the car to the dealer. They said they would charge $200 to diagnose the problem I agreed. Then they told me the problem could be PCM, Harness, sensors, fuel pump, fuel injectors or electrical problem and maybe more of a big job too. They said it could be one of them, some of them or all of them. If I wanted to know exactly which one, they said I have to pay another $200 for more diagnosis. I thought I would get the results for the first $200 they didn’t say in advance that there might be more to pay for further diagnosis. They are rip off I pay them $200 and took the car without knowing what exactly is the problem.
I bought Haynes Repair Manual to trouble shoot myself. I see that there could be all kind of problems for the car to stall meanwhile driving. It needs to check bunch of things like vacuum leaks, relays, fuses, sensors, compression, injectors, harness, PCM, wires that might touch the chassis and make short etc. I checked for relays and fuses they were ok. I cleaned the throttle so far. When I drove the car it stalled after 20 minutes in the middle of a drive, I tried to restart it and it did restart but driving with hesitation and no power also I had noise coming from the muffler for the first time. I think it was misfire noise from the muffler like pot pot pot. And for the first time the speedometer stopped working when driving and airbag light came on the dashboard. I am thinking electrical problem. I opened the hood the engine felt pretty hot but the water didn’t boil in the reservoir and no antifreeze was spilling the reservoir looked ok. I am thinking that when the engine gets hot the car stalls. It’s not overheating because the car stalls if it didn’t stall maybe in a little while the car would have overheat. So I am thinking if the car didn’t get hot it wouldn’t stall. Instead of looking which sensor, injector, short on the wire or to blame the PCM, I have to fix the car to not get hot, then it won’t be problem. Does anybody agree with this? Whay the car stalls after 20 minutes? Because the engine is hot.
From the forums I read one guy replaced camshaft sensor and it worked for him, the other guy changed the camshaft sensor and it didn’t work for him.
If I had the equipment to check the sensors, the vacuum leak, fuel pressure, fuel injector pressure and all that, I think it will all show ok because when I start the car for the first time of the day it’s all good, so it won’t show any problems with the test, if I check it when the car is hot, and it shows say problem with a sensor still doesn’t mean the sensor is bad, because maybe when the car is hot the relay that sends signal to the sensor is not working right, because of the heat the relay maybe malfunctions. I can’t blame even the relay because maybe the PCM is not working right because of the heat, I can’t even blame the PCM because the wires are touching some hot surface and shorting the PCM.
Nobody has mentioned in the blogs to keep the car from running hot. Why the car runs ok for the first 20 minutes of the day and what happens after 20 minutes? The engine gets hot. Why blame the sensors or other parts, why don’t blame the cooling system?
When the car was cold I started the car opened the radiator cap and looked at the water. The antifreeze was green all the way to the top water wasn’t circulating, I guess it wasn’t supposed to circulate yet because only when the engine is hot then the thermostat will open and let the antifreeze circulate to the radiator to cool it off. I put the ac on, then the coolant started to circulate and the radiator fan came on so far looks ok but the coolant plastic reservoir was full and coolant wasn’t going in or out of there, when the engine is hot the coolant reservoir always full never goes down or up. I think this is a problem. When the radiator is missing coolant it takes coolant from the reservoir and when the engine is hot the coolant goes back to the reservoir. Looks like this is not happening, so maybe the radiator cap is getting stuck and not letting the coolant back to reservoir and engine gets hot? Maybe the water pump doesn’t have enough pressure to circulate the coolant? Maybe the thermostat stuck closed so coolant doesn’t get into the radiator and the engine is getting hot? The radiator looks physically clean from outside and no damage to it. There is no coolant leak and the hoses look good.
So I should ignore all the codes below and just concentrate to run the engine less hot?
So I checked the codes that the car gave me on the dashboard (with the ignition key on off on off on)
Codes I got:
508-Idle Air Control Valve Sense circuit low
032-O2 Sensor 1/1 Heater circuit high
038-O2 Sensor 1/2 Heater circuit high
300-Multiple cylinder misfire detected
August 24, 2011.

You gonna have to break this down to the nearest lowest term-I'm confused make it as simple as possible-

Aug 24, 2011.
After driving the first 20 minutes of the day (meaning the engine is totally cold not driven overnight), meanwhile driving the car stalls. Then I start the car right away and it starts. But this time hesitates and stutters, the speedometer fall to zero, the airbag light comes on. If I shut off the car for a while and start the car to take another drive say after 30 minutes, this time the car stalls after 2 to 5 minutes then it refuses to start until I let the car sit for 30 minutes or 1 hour.
These are the codes that the computer shows: 508-Idle Air Control Valve Sense circuit low
032-O2 Sensor 1/1 Heater circuit high
038-O2 Sensor 1/2 Heater circuit high
300-Multiple cylinder misfire detected
So far I changed: Air control sensor – 2 oxygen sensors – spark plugs – wires- air filter – cleaned the throttle with carburetor spray – checked the fuses and relays they are all good. Checked the radiator fan it works.
Any suggestions?

Aug 24, 2011.
Did you ever get your PT problem fixed? I'm having almost the EXACT symptoms.

Please let me know what fixed your issues.

Feb 5, 2013.