My Passat only upshifts and downshift at high speeds/RPMs when in Auto Mode

have you checked the fluid level?

I have not as checking the trans fluid is not a quick task in these cars and my jack stands are in use by my 65 comet. To check the trans fluid, the car has to be raised for access, level, and running with trans at operating temp to check the level at the fill bolt on the side of thing.

The car hasn't shown any signs of slipping though.

Have it scanned for transmission codes and check the fluid pressure.

also trans box under pass seat may have wiring/plug corrosion.

I just found something about that when scouring the forums on passat world, I'll check it out tomorrow and post an update!

I pulled the carpet up today and found the box housing the tcm. There is no signs of moisture ever getting down there and the wiring/box looks like new. I have ordered a obd/usb k-can cable to further help with diagnostics. I will take a picture of the box and wirings and submit them this afternoon

We'll be waiting.

So I know this has been a while since this was last visited but things have been a little crazy. I'm still trying to chase this problem. Since then I've had it scanned with a VAG-COM, no transmission codes. I've also done a filter change. The problem seemed to have lessened for a few hundred miles after the filter change but it could be coincidence. Based on that though, I'm considering having a transmission flush done. What do you think?

Also I was unable to relocate the info about the harness going to the TCM, what should I look for?

Thanks!

How many miles on the fluid? What does it look and smell like? Is it red, or is it brown?

I'm assuming that, with the exception of the fluid I added during the filter change, the fluid is the original. It was not red at all. It was more brown than anything. The car is sitting at 117k miles now.

Yeah, flush it. Brown is bad.

I took the car to VW for a flush and they do not do flushes. They said flushed have a tendancy to be followed by more problems or failure altogether. I did find out that the transmission fluid was actually fine. The tech was kind enough to bring me to the back and compare my fluid with fluid from a brand new sealed bottle. The fluid that VW makes to put into these trannys is brown brand new. I described the problem to him and he believes that it is a solenoid in the valve body that is getting weak. He explained that it could be worn out to the point where it doesn't respond to the electronic pulses sent for regular shifting but that the pulses for tip mode are longer so it still responds to them. Made sense to me, reminded me of having to adjust pulses on an aftermarket keyless entry system to trigger factory locks. He said replacing it is a job that anyone who know his way around a car could do but I am unable to find such solenoid. Would you have any insight about this solenoid or where i could find it? Thanks!

No. I wouldn't not off the top of my head, and I'm unable to access our online reference material at the moment,

However, the valve body is easily reached by draining the trans and then pulling the pan. But he is correct. A worn solenoid can cause what you're experiencing.

If the fluid smells like something that's been overcooked, it has.

Hi, would there be any way to find out what the solenoid is that I would need? I know you were unable to look it up last time but I just wanted to ask. Also, I can't find the flippin donate more to this question button. How do I do that?

I just looked through our reference materials for about an hour and couldn't find any mention of the solenoid. It's an electronically controlled that is usually located under (above) the valve body in the transmissions I've worked on. It might be somewhere near where the input speed sensor is.

I'll let the admin know you're looking for a "donate again" button. Thank you.

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