Passat TDI: Higher Idle Speed in Newer 130PS Models?

Hello!
'Yesterday, I attended a winter driving training. There were three Passat Variant Highline models with 130PS TDI 4Motion engines present. Interestingly, all three had a higher idle speed than mine! In those cars, the needle was exactly between the 1000 mark and the one below it. My needle is exactly aligned with the mark below the 1000 mark. Why is that? Could it be related to the 4Motion system or the Passat's tendency to be slow to start, or did VW reprogram the engine control units of all 130PS models (including 2WD) to reduce vibrations when idling? Could you please check yours? My workshop once offered to increase my idle speed. They said it's supposed to be quite easy!'

Greetings.

According to VCDS (Vag-Com), the idle speed is 830 RPM, which is quite close to the mark below 1000 RPM. However, according to the manufacturer's specifications, there is a tolerance that allows for an idle speed of slightly above 900 RPM. The adaptation process is quite simple! Please refer to MichaelII's article on this topic for more information.
What might be related to 50 revolutions per minute (RPM) with or without vibration, or with a weak start, remains unclear to me. Do you think changing it to 50 or 70 RPM would make a difference? I don't think so!

My 130 model also has a factory-set speed of 890 RPM instead of the maximum allowed 870 RPM. The speedometer is quite inaccurate when it comes to measuring speed.
The intended range is approximately 790-870 revolutions per minute (RPM).

"On my Golf 130, the tachometer needle always sits between the 800 and 1000 marks. However, according to VAG Com, the idle speed is always between 790 and 880 RPM, which seems quite normal. Nevertheless, this also indicates that the tachometer is quite inaccurate."
"However, what frequently happens with my car when idling before it reaches operating temperature is that it stutters. As soon as you give it even the slightest bit of gas, so little that the fuel consumption doesn't even increase, the stuttering completely disappears. Perhaps VW increased the idle speed slightly on their cars for events like this...?"

'I'm not familiar with that kind of shaking. But I also experienced similar vibrations with my 1Z engine. Increasing the speed by about 50-70 RPM didn't help much. It took an increase of about 100-150 RPM to make a difference.'

Hi Jörg, it's possible that it's different with PD engines. Meier runs relatively smoothly within the diesel technology parameters when it's warm. However, below a certain outside temperature (somewhere around 10 degrees Celsius), and when the engine isn't fully warmed up, it has a noticeable vibration at idle that I haven't experienced in any other VP TDI. It's also not something that bothers me, and as I said, it completely disappears with even the slightest amount of throttle. I don't know the exact RPM, but I think the difference remains below 100.

@joergs!
'50U/min can already make a difference! But for the sake of comparability, only Passat drivers with the AVF engine (130PS) should respond and actually refer to the tachometer markings. The 3 TDI engines were exactly BETWEEN the markings, mine is 100% consistent with the lower marking. I want to find out what's causing this. Is it the year of manufacture, the 4Motion system, etc.? All the 4Motion models were among the last ones produced! Mine is from 05/2002 and is a 2WD. It would be great if you could write down your year of manufacture and whether it's 2WD or 4Motion, and also where the needle is pointing at idle when the engine is at operating temperature.'

Greetings.

Hi Mike,

My tachometer is also at the first mark (800) below 1,000 RPM, whether the engine is cold or warm.

Regards,

Rudi.

Hello Rudi!
The 3 4Motion vehicles at the driving experience event ALL had the needle exactly in that spot! Of course, I don't know what RPM that corresponds to. Does anyone know how many RPM the area between the two markings is on the Passat?
'However, since all 3 exhibited the exact same behavior, I don't believe it's a coincidence. I suspect that VW has adjusted something related to the standing vibrations, especially in the summer when the air conditioning puts a lot of strain on the engine. Now, in the winter, my steering wheel doesn't vibrate at all, whereas in the summer it vibrates very slightly.'

Greetings.

PS: I'll probably go to the dealership today because of the air filter housing.

'On my Passat, the idle speed is 200 RPM from one mark to the next. On mine (which has an AWX engine), the idle speed is exactly 830 RPM according to VAG-COM, and the needle is almost perfectly aligned with the mark just before the 1000 mark (so, 800). If it's somewhere in between, it should be 900 RPM. If you factor in the observed tolerance, you're over 900 RPM, which could potentially be problematic. I believe the tolerance was around 920 or 930.'

Hello!
As I said, all three test cars had the needle exactly BETWEEN the markings. So, that should be approximately 900 RPM, right? It can't be a coincidence anymore if three cars show exactly the same behavior. My gauge is perfectly aligned with the last marking before 1000 RPM!
Is that an AWX? Is it a 100 hp TDI engine? Or what kind of engine is it? I believe the Passat only came with the AVF 130 hp TDI engine. Or is it the Superb engine with a 5-speed transmission, which has 130 hp but only 285 Nm of torque?

Greetings.

No, the AWX is a 130 hp diesel engine, and it was definitely produced for quite some time. This engine was fitted with a 5-speed gearbox and had a torque of 285 Nm. This engine was used in all 5-speed models until approximately June/July 2001.

Okay, I'm familiar with that. However, it was never available in Austria! They only ever offered the 6-speed version. But it *was* available in the Superb!

Greetings.

@MikeF:

It's just an idea, but did the test vehicles run with cylinder deactivation in automatic mode?
I have a feeling that the idle speed might be slightly higher then.

Yes, all 3 were running on AUTO, including mine (and this was the case throughout the entire year), and the temperature was between 0° and -4°! So, NO compressor! Therefore, the conditions were and are identical!

Greetings.

Here's another addition: The current fuel consumption reading at the pump (L/h) also showed this. It displayed 0.9 L/h for the 3 4Motion models. In my case, it's 0.7 L/h.

Greetings.