Engine Problem of my 2000 Cirrus
 

My 2000 Chrysler Cirrus has a kind of engine problem. Just one day after the mechanic repaired its transmission problem and overfilled the coolant tank, I traveled from New Jersey to D.C. On the way, after nearly 2 hours, the overheat light turned on. I stopped the car and waited for the engine cool down. When I checked the coolant water I saw that it was not boiling. After the engine cooled down I started to drive engine and turned the heater on to help the engine keep cool. But I realized that cold weather was coming from the heater, although I selected the hottest level. After I read the manual of the book I discharged some coolant water. After I did this, I had the similar problem again but this time the water was boiling and I got hot air from the heater for a short time. This problem occurred 5 times on the way to D.C., but each time I waited for the engine cool down. I did not drive it while the engine was overheated. In the night of the same day I traveled back to New Jersey and after about 3 hours same problem occurred and this time Check Engine light flashed and the engine started to shake. So, I stopped my car and it was towed. My mechanic told me that it is a really big engine problem and it costs around $3,000, which is almost the price of my car. Does anybody know any mechanic in North Jersey that can help about this problem? I really appreciate any advice about this situation. If there is anyone interested in the car, I will sell it for $1,800 as it is. It has a clean title with 89,000 mileage and I was very happy with my car until this problem.