arhy

Hi everybody!

Thanks for all your previous help!

Got a 04 A6 2.7T S-Line with Tiptronic (determined by the code in the spare wheel compartment after lookup). My transmission has been acting up a bit, especially in summer time. It all started about a year and a half ago afet a long trip to California. Suddenly on hot day, after being stuck in slow moving traffic on the freeway, when accelerating back to higher speed, the tranny got stuck in 3rd gear and then PRNDS was all red. Pulled over and waited a few minutes and the it went away. Didn't give it too much importance i just drove the car.

A year later same thing happend after being stuck in slow traffic in a 95 degree day. I also noticed rougher and rougher shifts in summer so I took it to the dealer. Guys in Idaho Falls kept car all day and told me they added half of quart of oil. Problem went away for six months and then came back a little worse. So a this last summer I went back and I was told the valve body needs to be replaced.

Also, in summer time if I don't drive the car, but i keep it running in the parking lot for 5 minutes lets say and then I drive, the shifting is very rough. Feels like someone actually crashed into you from behind.

I check with my VAG cable and I have no error codes under the transmission module. I was also in the car at the dealership when the mechanic checked and he couldn't find any codes either.

Now I got the money from the extended warranty and I have enough to do a rebuild on the valve body + an oil change. I found out that Level 10 or IPT do a pretty good job from what i read on the forums. Called Level 10 and the guy said he needs a code in order to know what's wrong, but I have no code....

Has anyone experienced such problems? Is it worth replacing the valve body or shoudl I just change the oil? What do you guys suggest I should do? I just went past 100 000 miles.

Thanks for your help!

tester123

I am no expert in these matters but, did you ever try resetting the ECU as in disconnect the battery for about an hour or so and try to drive again slowly? This could reset the adaptation. Also, trans oil/filter change could help. My bro's '06 Passat was acting up similarly and we changed the oil and now it shifts like brand new car.

devinsixtyseven

What's the mileage since the last transmission flush?

4Driver4

Hopefully it's never been done.

Fluid and filter should be changed. No flushing.

devinsixtyseven

Semantic clarification...when I say flush, I mean change all the fluid, and that's it. No other products, no forcing anything, just drain the old fluid entirely, and replace with new.

MP4.2+6.0

1. Reset the TCU and throttle both. Search archives for procedures. Don't think a battery disconnect does it.

2. Yes, do a fluid and filter flush; might help clean up valve body.

3. Look at the MAF. It interacts with the throttle position and tranny shifting. If by chance car ever had a K&N filter in it, figure the MAF is now very suspect or toast given your overlapping shifting problems. Can be tested for measured flow if you have a VAG COM, but if never touched you may just decide to replace it for a rebuilt one (basically new sensor in a reused tube). BTDT.

4. Look at the output sensor and the wiring from the TCU to that sensor. BTDT and had many of the issues you describe along the way. Also rebuilt the valve body. Mine had a intermittent wire fault between the TCU and the sensor. Almost sheer chance I found it, and only by instrumenting it with VAG COM on a short test drive and monitoring the sensor. Once I wired around it, problem finally solved after several years of exasperation. If this is pretty shorthand, for reference the output speed sensor is the feedback loop telling the ECU and TCU what the tranny is outputting. If the feedback gets corrupted of course, bad behavior results. Clunk is typically the car suddenly deciding it should be in a way different gear, or maybe even inconsistent gears in short order. Often results in the reversed display when the tranny goes into SAFE mode until you restart it.

5. Finally, yes maybe the valve body if you work your way down the prior list. When I did mine, it didn't fix the problem on a lasting basis (later proven out to be the bad wire to the output sensor), it did make the shifts really nice and precise. It had gotten kind of sloppy over the preceding years.