Please Help! Ac/overheating Issue.

[SavageLady]

Hello, I have a 2002 GT and I'm having an issue ever since I started my 2,400 mile move to Texas. It started overheating half ways to Texas and I stopped at a shop that I forget the name. They changed the thermostat and fixed some bolt that they broke. I left and continued to overheat so I ended up going back a total of 3 times until he told me that I should replace the entire AC. He told me this because it ONLY overheats when I have the AC on and am going slow or at a stop. If I'm going at a steady pace above 35 it doesn't do this. And ever since it overheated the first time, it's made sort of like a whistling sound when I accelerate.

So I end up changing the AC compressor because he also mentioned this, and that did not work. Well today, I changed the water pump and it still does it! So can it be the radiator, or what other problem could it be? Anyone that has had this issue and fixed it?

I don't know anyone here and I'm sick of going from mechanic to mechanic here for them to just tell me to put water in it. Obviously that isn't the problem because this would have been done and over with. I'm seriously dying in this Texas heat.. And dread using my baby to get around! Please help!!

 

[Kilgore Trout]

Sounds like your electric fan is broke, do you ever hear it spin up? It should come on when the engine is hot real easy to hear when you pull into your garage. Check the electric fan fuse and listen to hear if it is working.

 

[SavageLady]

Yes, the fan works.. It turns on once my heat temperature turns half ways.

I'm feeling pretty desperate with this whole thing right about now!

 

[wmburns]

+1 on above. Sure sounds like one or both speed fans isn't working. Remember that the GT/Cobra has a two speed fan. The low speed runs when the AC is on. The high speed runs when the motor is above a certain set point.

The first step should be to verify that the fan runs when powered directly from battery. Test BOTH speeds.

Is the radiator clean on the inside and outside?

Have all of the fuses been confirmed good?

Does the fan run if the coolant temperature sensor is disconnected?

If it does, this proves the CCRM is good. Then we will need to know what the PCM "thinks" the engine temperature is. An ODB2 scanner is needed.

If not, likely the CCRM is bad. I have posted several times how to trouble shoot CCRM issues.

A set of wiring diagrams will help trouble shooting electrical issues.

 

[SavageLady]

Oh my.. Thank you for all of this info! Will taking it to a Ford dealership for them to do a computer check tell me the answer? I usually do ALL work on my car, but I think I give up Lol

 

[wmburns]

Considering taking to the Ford dealer when you normally do all of your own work? Giving up before the fight has even really started are we? Especially considering how much $$ you have already spent with "professionals" without an actual "fix".

You can do this. Or at the very least, you can get a better idea of what the problem really is so that you will "know" if the next mechanic to "blowing smoke" up your private parts.



You will be surprised what can be done with a good set of documentation and a methodical approach to problem solving.

Question? How much $$ has already been spent on this problem? I bet the cost of wasted repairs could have easily bought a top of the line ODB2 scanner. IMO, most home mechanics don't need a top of the line ODB2 scanner. A mid priced unit will do. For the serious $$ constrained, most auto parts stores will RENT the tools.

 

[SavageLady]

I have spent my fair share. Considering that I'm almost 8 months pregnant and just moved from WA, the rainy state.. to Texas, where it's hotter than hell.. Yes, I think I give up this time.

Not sure I want to bring my baby home in black leather with no AC. Or attempt to fix it right now.

And I don't think the repairs I have done are wasted. Most of it was original parts any how. Better to get it done before it fails on me

 

[SavageLady]

Please understand I would not normally give up so easily.. But I think I should this time? I will however invest in the scanner once I move next month. Any recommendations?

 

[wmburns]

I'm not sure that I agree to have paid for a NEW AC system and still have a non-functional AC. I would be completely besides myself to have paid for a "professional" to resort to wholesale "parts changing" in an attempt to find the problem.

Normally one expects to pay more for a professional to work on your car. But in exchange I expect to get an honest diagnosis and repair of the problem. From your description, it's only looks like a felony has been committed with your OK.

However, you have higher priority issues besides fixing your car. Good luck to you.

 

[SavageLady]

I changed the AC myself. But it continues to overheat when going slow or at a stop.

I payed a professional when I was broken down to change the thermostat because that's what he thought it could be. I couldn't afford the EXTRA $900 for him to do the entire AC at that time, so I continued on without AC.

I'm just curious if the dealership can diagnos the actual problem instead of guessing what it might be.

 

[01cobra aka silversurfer]

I would reccomend doing a coolant flush....ive sen coolant galleys in heads clooged from rust and crap and and that blocks the coolant from circulating properly resulting in overheating and headgasket blowing and headwarping..where in tx? im in dallas if u need help

 

[wmburns]

+1 on checking for a clean radiator. I'm very much in favor of always covering the basics before digging deeper.

I'm hard pressed to think of any circumstance where an AC problem could cause a car to overheat. Short of a non-functional cooling fan or blocked air flow through the radiator. Which if true would be a cooling system problem. Regardless, if the AC load causes the motor to overheat, then the cooling system is MARGINAL to begin with.

Are you aware that the PCM turns off the cooling fan when the car's speed is above 45 MPH? The cooling fan could be totally non-functional but as long as the speed is 45 MPH or higher, the motor will not over heat.

To me the fact it runs OK at highway speeds but over heats in stop and go traffic strongly points to a cooling fan issue.

The AC on the other hand requires the low speed fan to run all the time when the car's speed is below 45 MPH. The AC can not work without cooling air passing through the coil.

Does turning on the heater full blast stop the motor from over heating?

Does the cooling system hold pressure? What is the anti-freeze percentage?

When the car does overheat, how fast does it happen? In my experience, a car that slowly overheats is a clogged radiator. If it happens quicker, it's a fan or T-stat.

 

[SavageLady]

The coolant is brand new, I flushed the whole system already. And checked fuses like you said and they are all good.

It overheats slow enough that I can catch it before it's too late. To stop it, I just turn off the AC and it's good.

Thanks for the offer 01cobra, but I'm in Palmview.. Far south lol.

 

[SavageLady]

I'm going to try the radiator next. They will charge me $100 to clean it if I bring it to them, but I think I would rather go brand new. It's already 10 years old anyways, mine as well go new, right?

 

[trinity_gt]

Does the car have underdrive pulleys?

 

[SavageLady]

That's aftermarket, correct? If so, then no.

 

[Kilgore Trout]

God damn you sure are throwing a lot of expensive parts at the problem. The whole story almost sounds like made up bull... Tell us again how you changed out the ac by yourself, be specific...

 

[trombonedemon]

When you say you are overheating what exactly is happening, my car posted its hottest temp of the year today at 212 degrees F and it almost never goes above 208 F, but like you, my A.C. was on.

Was the car spitting fluid all over the place? Was a head gasket blown?

P.S. 208 is when the fan starts to function under the cruising speed.

 

[01cobra aka silversurfer]

did you ever get the issue resolved Savagelady?