Problems with Upshifting 722.9 7G-Tronic Plus

[Mersovod]

Most likely, the author of the topic turns off the boost, but the engine degasses and there is a drop in power, so the gearbox works inadequately. Another common problem is the wastegate damper sticking, so the emergency mode is activated only under active acceleration.

 

[User]

My pressure is currently around 2 hPa at idle and 0 hPa with the ignition on. Is 2 hPa too low? Does this indicate cr@cks in the DPF?

 

[Mersovod]

Unlikely. What is the soot content calculated based on actual values? Pressure sensors parameters? What are the opening mode? The burning interval is approximately 200 km in the city, 800 km on the highway. Check out the history and reasons for stopping DPF burning.

 

[Blackronin]

It is unlikely that the DPF is faulty, although the codes will point directly to this. I'm guessing the dealer told you the car was held in low gear for regeneration purposes, based on the sounds, based on the fact that they forced regeneration while it was there. When attempting regeneration, the vehicle also changes idle speed and gear shifting. Have you also noticed an increase in idle speed? I would try driving it a few miles on the highway to see how it handles. I'm not entirely sure about the distance you need to travel at higher RPMs, but on American trucks it's about 50 miles. I hope this helps you at least a little.

 

[User]

Today I tried the test drive again. When I start to accelerate smoothly and constantly increase the power, it shifts comfortably up to 7th gear without unnecessary delays. But when I press the gas pedal quickly (in 7th gear), and not even in kickdown position, the transmission stays in 4th or 5th gear and the revs are almost 4000 RPM, and the upshift still does not happen, even if I drive longer at the same speed. But if I turn on cruise control, it immediately switches to 7th gear.

I think the sound was coming from the pipe connection between the turbocharger... there was a missing O-ring. After the repair, I opened the hose and checked.

 

[Mersovod]

Often mechanics lose or damage this ring when replacing the fuel filter. During the first 15 minutes of driving, the car may jerk when accelerating smoothly. Then no. In this case, no fault codes are registered.

 

[Tom PPP]

The problem may be in the automatic transmission and speed sensors N1, N2, N3, there is no error, since one of them is slightly distorted. There may also be a problem reading the wheel speed. You need to drive the car and observe real data.

 

[lmdtm]

Have you already reset the adaptation?
A simple reset, which can be done without XENTRY, will clear some internal transmission errors.
A DPF failure may cause the vehicle to enter limp mode, but this will only limit engine speed and turbocharger geometry, not transmission gear retention.

 

[User]

Thanks for all the advice. However, I think the problem is a faulty DPF. It's faulty because soot gets through it.
With a larger outflow, the ECU disappears from the map. And because of this, the gearbox does not shift as it should. With less outflow, the gearbox works as it should, and almost no soot is formed.
That's my opinion. I already have a new DPF and I am waiting for it to be installed. We'll see if the situation improves after the replacement.

 

[lmdtm]

Let us know if this solved your problem.