My friend's 84 Omega is fine when its cool, but after running for several minutes (maybe 30) it stalls whenever its stopped and in gear. He says it behaves as though its a manual and you forget to use the clutch. I dont know if it has a TH125 or a TH125C, so I dont know if it has a TCC or not. Is this a common problem, does anyone know what it might be?

 

Replace the Lock Up Solenoid. This is a common problem- so common that I replace the Solenoid on all 125C's that I do.

 

I have dealt with far more TCC solenoids than I have all other problems with 125's. In fact, I rarely ever see any other problem with a 125.

I'm 98% sure it is the TCC solenoid.


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I also agree. While you have the side cover off, replace the gear switches because they like to set codes.

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Can I get at it without dropping the transaxle? As long as we're on the subject, is this a common problem with 440T4's as well?

 

Yes you can get it off in the car. You will have to take the side cover off as that is where the Valve Body is located. It is held in place with a Torx bolt.

This is not a common problem on 440-T4's. They have a whole grocery list of their own problems!

 

I don't mean these exact symptoms, but TCC solenoid problems in general. I have another car with a 440T4 that shudders badly trying to make a 4-3 downshift, but seems to behave itself on a 4-2 downshift.

 

CHeck this first: Take the vacuum hose off at the modulator while the engine is running and see what happens. It should either speed up, run rough or stall. If nothing happens or hardly anything then the vaccum line (probably right inside the manifold) is carboned up, restricting vacuum flow. THis in turn doesn't allow pressure to rise quickly in response to engine load changes. This is a very common cause of failure on the 440-T4. If this is the problem, take a small drill bit and by hand, clean out the passage. It is also possible that the 3rds are slipping or even the 2nds (they take the most pounding as from seconed gear on, they are the drive clutch). ALso add 2 quarts of oil, even if it is to the full mark hot. These trannies desperately need more oil for both lube and cooling problems, but also to keep the filter covered during different manuevers. If the oil is dark and stinky it is likely that the tranny is gone.

 

Did I hear you right? I thought that it is bad to overfill a tranny. Won't this blow the seals out or make the fluid bubbly?

 

That all depends on the tranny. THIS tranny NEEDS it. A 400 usually wants a little LESS than full. Many of your O/D FWD trannies seem to need this too, by the way.

 

good day to all
new in the forum
have a problem with daewoo racer 97 with gearbox th125c , 3 gears,
goes up to 60 ktms speed and then gearbox neutralizes , does not go to third gear, replaced fluid bt no positive result , any suggestion to check before remove the gearbox fm the car?
tks in advance