2003 Overheating on short trips | Ford Thunderbird club group 1955-2005 T-Bird models

2003 Overheating on short trips

JBond007

JBond007

Reaction score
7
Thunderbird Year
2003
Hi everyone, I recently had an issue with my car pegging HOT and temp light coming on after a very small trip. Have 40,300 miles on it. 5 min drive to store, inside for an hour and 5 min drive home (happened after 2 min) and was going to pull over but I quickly shut the a/c off to reduce the load and temp started dropping right away, light went out and got home with gauge showing smack in the middle as always.

I raised the hood and looked around. Saw that the upper radiator hose has a dry white corrosion and a wet leak on the top of the plastic tee connector. After car cooled checked fluid level and it was down about 20 oz. I have Gold in mine so added the premix gold to get it to the cold level. I took it to mechanic and they changed the hose out to a Dorman with metal tee connector for future protection from cracking. They said they bled the air out. Got home with it and all seemed good. In the morning saw like a 3" puddle under overflow tank directly down to floor so thought they put lil too much fluid in. Went for 5 min ride, reached normal temp, car sat for about 1.5 hrs, drove 5 min more and car sat for 2 hrs and saw 2 spots about 2" big in friends driveway. 5 min to home after, temp gauge still good thru all this. Parked in garage, went in for 10 min, came out and saw this giant puddle under the car ( clay litter on some but couldn't get to the other part). Again dripping down from the overflow tank only. Called mechanic, sent them pics, owner came to my house and said still has air in system so he filled it and I drove it to them. They bled it again and manager wanted to change the thermostat but I declined since owner said it was just air. He said fan and thermostat was working fine. Manager changed the cap on the overflow tank saying the spring was weak and they ran it for an hour and all good. Car sat for 3 days with no issues. 4th day drove it 5 min, sat for 1.5 hr, 5 min home - all good no leaks. Sat for a day, no leaks. Next day, 5 min drive, sat for 3 hrs, 5 min drive home. In morning had about a cup of fluid on the floor again. What the heck is going on?????

I saw an old post but it didn't have any replies to it about possible "Bad PCM" (title of it, they had 03 with coolant leak too)?

Look forward to your thoughts.

***Pics: 2 with old upper, leak after

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I went through the same thing on my 2004 last year. The white residue is the coolant leaking through the micro cracks from your injection molded plastic coolant components. My recommendation is to change all of the coolant system components including the rubber hoses including the degas reservoir as shown in the attached diagram while you have it apart. I serviced my serpentine belt while I was at it, One important thing to note, change the coolant tube that runs underneath the intake plenum. I missed that line when I had my intake off. It goes together faster the second time! (ha ha). This molded line is not available, but that is not a problem. I inserted tubing inside the rubber line to hold the shape to avoid kinking the line. There are some You Tube videos that show how to change some of the components without removing the intake manifold. It is your call, but I recommend just do it right and lift the intake manifold since that is the only way to access the tube that is under the plenum. after you have that lifted up, it is easy to access the bolts to replace the injection molded parts. If you work on cars, you will find it is not hard, there are some very tight access areas, it just takes time. I also recommend replacing all of the clamps while you are at it. Some viewers may have been fortunate to successfully reuse the factory clamps, but several of mine lost the clamping force and started leaking, so I ended up changing all of them. I added a couple of additional photos, I found the photo of the line under the plenum, I also label all of the lines and electrical connections to make it easier during assembly.
diagram.jpg
 

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The most common crack is in the thermostat housing which should be inspected carefully. Also, this cooling system is much harder to bleed air from than a typical car.

This thread has all the common parts-

Here's a video with some coolant system burping / bleeding tips on the "cousin car' Lincoln LS. Would be great for a member to make a Thunderbird specific video and send to us to add to our YouTube channel!


 
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