4 Speed Automatic (tiptronic) Problems

[pt-auto]

Hello!

 

This is my first post to this forum and I could really use some help with my '01 Galaxy 2.3 4-speed tiptronic. I am trying to fix the gearbox problems with a budget that stills allows my family to eat some cheese on our daily bread..

 

Ford TIS says in the AG4 gearbox solenoid test table that solenoid 4 (Torque lock-up solenoid) should have a resistance of 55-65 ohms. My galaxy has solenoid 4 with only ~5 ohms. The solenoid is ok, I removed it and checked the operation with a jumper wire (it did pull). But should there really be a solenoid with a resistance of 55-65 ohms or is this just an error in the TIS documentation?

 

The symptoms in my galaxy are:

 

1. When shifting up it like changes to neutral and revs for a moment. Sometimes it also makes a noise that is a bit hard to describe, but resembles the sounds of a slightly slipping rubber belt.

 

2. Fourth gear slips very easily. I think it is really slipping, unless, due to some error state, the box changes very quickly between neutral and fourth gear when accelerating/releasing throttle.

 

3. Check engine light comes back on soon after clearing the codes. The code is (if I remember the exact phrase): P0700 Transmission control system fault (Mil request). There are no other codes.

 

What I have done so far:

 

1. I soldered a new capacitor to the TCU, beacause at one point the box went into emergency mode with only gears 2,3 and R available. It was just a wild quess, but it seemed to work, I got all the gears and tiptronic back to operation. This did not help with the other problems though.

 

2. I changed the gearbox oils twice in one week. Both times the oil was black but smelled roughly the same as new dexron III oil. I changed the filter also and cleaned the sump magnet that had maybe 2 millimeters thick layer of gray soft metallic substance over it (friction material?)

 

3. I removed all the solenoids, checked their resistances and cleaned them with brake cleaner. None of them was broken and they all rattled nicely when shaken. As mentioned earlier, solenoid 4 was however not the kind of solenoid that TIS documentation says it should be??

 

I would really appreciate it, if someone could give me some good advice!

[pt-auto]

OK, here are some more questions. Please answer, if you have any knowledge at all on this topic.

• Has anyone had any problems with the four speed tiptronic?
  
• Is it common for the solenoid valves or the valve body to cause trouble?
  
• Or is it common that the tcu is faulty? Is there any way of troubleshooting/fixing the tcu if the easy bits (solderings and capacitor) are ok?
  
• Is there an easy way of diagnosing a torque converter lock that won't lock?