Automatic Transmission Problems: Weak Performance

Hello everyone,
I have a VW Passat 1.9 TDI with 81 kW and a 4-speed automatic transmission.
I had the chance to drive a Passat over the weekend with the same engine and manual transmission. I noticed that the manual transmission Passat performs much better (acceleration) than mine http://mysmilies.no-ip.com/mysmilies/firedevil_2.gif. Could this really be due to my transmission?
Thank you for your opinions.
Best regards, Florian.

Hi,

"As a test, I temporarily reprogrammed the engine control unit of my AHF (110PS TDI) to automatic mode. While this eliminated the unstable idle speed when rolling (which could be addressed in another way, but costs power), it also disabled the jerk-dampening function."
After I subjectively found the suit to be significantly worse, I immediately put it back.

Best regards, Rainer.

Hi everyone!

Here's the translation:

'I've noticed the following with my AJM (115 hp, common rail) model with a 5-speed Tiptronic transmission:'
After a brief period of idling, when I accelerate again (in a right-of-way situation), it takes about 0.5 seconds for the engine to respond to the accelerator pedal.
Is this related to the automatic, vibration-dampening feature?

Best regards, Jürgen.

Juergen wrote:

... Here's the translation: "I've noticed the following in my AJM (115 hp, common rail) with a 5-speed Tiptronic transmission:" After a brief period of idling, when I accelerate again (in a right-of-way situation), it takes about 0.5 seconds for the engine to respond to the accelerator pedal. Is this related to the automatic, vibration-dampening feature? ...

Hi Jürgen,

Unfortunately, no!
I'm experiencing the same problem with my 74kW PD engine.
Take a look at this /viewtopic.php?t=1507.

I have a 66kW ALH engine with a 4-speed automatic transmission in my Octavia.

I can't complain about the traction. It's almost losing grip in dry conditions, and in wet conditions, the traction control system (ASR) kicks in aggressively. (Standard tires: 195 size).

I could, just for fun, re-code the engine to use a manual transmission. I've tried that before (without paying attention to power delivery), but then the whole thing shifts like a watering can because the fuel injection amount isn't reduced during the gear change... it just jerks, jerks, jerks.

Racing against 318s is definitely not a topic.

CU Gremlin.

Hello King,

Okay:

1.) The extra weight...

A vending machine typically weighs between 100 and 120 kg.
A manual transmission weighs approximately 40 kg.

2.) The converter and the converter bridge coupling.

During gear shifts and when driving at low speeds with subsequent acceleration, the torque converter lock-up clutch is disengaged. This causes losses due to friction and flow resistance within the torque converter, as well as a significant amount of engine power being transferred to the torque converter, which heats the oil and consequently results in efficiency losses.

The torque converter coupling is never fully engaged when a gear is selected; it is always regulated to operate at approximately 97% engagement.

Performance losses again.

3.) The driving strategy.

The driving strategy is determined by the respective manufacturer (in this case, VAG).

Four-speed automatic transmissions are usually designed for comfort rather than spontaneity.

Greetings from Lake Constance.

Tobias.

Hello.

Could it really be due to a problem with my transmission?


Yes, also.

Rainer has already mentioned the attenuation for comfort reasons, and that's certainly a significant factor.

The second reason is that automatic vehicles weigh slightly more than those with manual transmissions (depending on the engine, 10-80 kg).

And the third reason, as you mentioned, is the transmission. However, at a top speed of around 190 km/h, the difference between the individual gears of a 4-speed and a 5-speed transmission isn't that significant.

Best regards,
Ernst.
edit: I seem to have started typing at the same time as my predecessor.