Logan00,
You need a new TC and a rebuilt and modified valve body. The parts will run about $400-500. You will have to do the work yourself (the install) since it is unlikely that you will find anyone that will be willing to do a partial repair.
Now for whatâ??s actually going on. The converter bypass valve (controls fluid pressure to the TC and TC lock up) is a defective design in the CD4E. Two other valves are also poorly designed and suffer premature ware and are responsible for controlling hydraulic pressure in the tranny. As the valves ware the pressures that control clutch engagement and TC lock up drop. This causes the clutch plates in the TC to drag and slip during lock up (just like ridding the clutch). This causes the disks to fail. With the TC not locked the fluid is heated to a high temp in side the TC. A second defect now comes into play, during lock up flow to the trans cooler is reduced. With no flow and an unlocked converter the fluid can boil! When you come out of lock up the hot fluid is sent back into your trans damaging the rest of the unit.
As a safety, the PCM detects the slippage in the TC and sets code 1744. It also sets the internal control pressure to 90 PSI in hopes of overcoming the problem, this results in Bang Shifts. This alerts the driver to the problem. Each time you shut the car off the PCM resets this 90PSI condition. This is why shutting the car off and restarting seam to fix it for awhile.
Why did I tell you all of this? Well if you keep driving your car you will destroy the rest of the tranny. If you stop and get it fixed now you can save big bucks. Also, flussing and additives will not help so donâ??t waste your money on them.
Oh, and donâ??t kick yourself over this. No amount (although Iâ??m sure to get an argument over this statement) of tranny maintenance can prevent this failure. It is built into the design of the VB and oil paths. My tranny was maintained and driven responsibly and my VB was shot at 87k mi.
What ever you do, make sure that your new VB has been updated with all the Sonax valves. SK-JR alone will not help at this point.
jeff