Sable 99 Overheating

[timetrax]

changing the ect sensor helped turn my fans on more frequent when the a/c is off. I guess the old one was bad. I decided to also change the temp sensor that is next to it and my problems came back, but just a little. I've come to another conclusion, that the fans aren't coming on enough while driving. But I have no way of checking that. I get that bubbling noise, followed by overflow at cap, but if restart the car and turn a/c on for just a minute, it will stop bubbling and overflowing. WHAT is this?? ANYONE??

update: I found a temporary answer here in one of the forums. Unplug the ECT, this will turn fans on full time when a/c not being used. You have to plug it back in for the a/c and compressor to work for cold air. The heater works either way.
SO! Can anyone confirm that on a 1999 Sable, there is no CCRM? ALSO, What controls the length of time that the fans stay on, when the a/c is off? I already have a new ECT installed. Would it be the fan relays themselves or the PCM? Does the PCM have to be changed by the dealer?

[rumorleigh]

I had an issue with my car overheating and they couldn't figure out what was wrong.. They did find that that the thermostat was bad they replaced that and sent me on my way.. A few days later the issue returned.. Only over heating occassionially. I could stop the overheating by turning off my air conditioner though.. The fix ever was that there was a bunch of dirt on my radiator after blowing that off with air. Just another place to look I guess...

[timetrax]

newer update: I switched the thermostat to a factory Motorcraft unit. This actually makes my fan cycle better. On for over 2 minutes and off for a minute plus. It was just the opposite before. So now it is getting better cooling, and no more bubbling / boiling noise. After that it was still overflowing through overflow tank cap periodically. So I switched to a Motorcraft cap and WALLA !! It long longer overflows through the cap. Every now and then it will spike and go back down, but at least no loss of coolant. I have been towing a lawn trailer, so I am going to put a trans cooler. This will take some extra heat off the radiator.
Now to find out why it won't turn over now and then. 2 auto parts stores say everything checks out ok. ????