High fuel consumption at 1Z, what should I do?

Hello,
Yesterday, I was still discussing that you cannot read the injection timing measurement block with VAG 1551. Today, it worked perfectly in another workshop. (The thread was accidentally deleted by someone). I was between the lower tolerance and the ideal value, so it's okay. I thought it might be this.
Fuel injectors are brand new, air filter, diesel filter are new, thermostat is new, engine has power, does not stutter, no noticeable smoke.
Estimated fuel consumption on country roads and highways: 8.5l.
This is definitely too much. I can't say exactly when I started having this increased consumption, as I only recently re-evaluated it after a long time.
Could it also be due to the timing of the valves?
I'm grateful for any tip, even though these topics have been discussed before, but in my case, many potential sources of error have been ruled out!

Greetings
Wurstblinker

-with Nothelle Chiplette-

Yeah, but not 2l more at once!
'I got the chip from someone who had one in the same car as mine, and they weren't getting this crazy fuel consumption!'
Even a slight increase in power, without increasing the turbocharger pressure, and approximately 10 horsepower more, which masks the turbo lag around 2000 RPM.

Best regards

Loose collection of ideas:
- LMM
- Securely tighten the brakes (are the wheels warm after a long drive?)
- other tires?
- another gas station? (not the one that tries to sell you BD...)

Good night!
Guste

driving habits!?
this is, in fact, the key!

Hi,
So, the fuel is from the same gas station where my brother also fills up his 66kW Golf 4 TDI. He gets around 7.5 liters per full tank when driving at full speed and with the air conditioning on.
The car drives very well, brakes are not stiff!

What tends to, especially with a high-mileage engine like this, lead to high fuel consumption?
Let's assume the boost pressure is 0.1 bar below the target value. Does this already lead to an increase in fuel consumption?
I disconnected the AGR by removing the hose and closing it with a screw. I also sealed the AGR valve with a small piece of hose and closed it with a screw. Is this sufficient? The VW specialist said that this might not be enough to completely close the AGR! -> higher fuel consumption?

Best regards
Wurstblinker

If so, you should seal the AGR with a sheet of metal. Increased fuel consumption can have all sorts of causes. The driving style is especially important. I was able to get my old 1Z to easily achieve 7.5l/100km. If you don't trust the settings like boost pressure, etc., then check them!

Hi,
I am currently in the process of a very strict cost-cutting exercise, meaning I will not be exceeding 2500 U/min, or allowing for any unnecessary idling.
I've also increased the tire pressure a bit.
Let's see what comes out!

Wurstblinker wrote:

Estimated fuel consumption on country roads and highways: 8.5 liters. Could it also be due to the timing of the valves?

Generally yes, but I don't know if / from what level of increased consumption additional "deceptive" symptoms would have to occur, such as: Starting issues, unusual performance development (primarily top-down).

Hi Ulf,
So, I will check the timing when the next instance of high consumption occurs! Looking up, he already seems a bit restricted, but it could also be due to the fact that he hasn't been tuned for that specific RPM range.
Where would you start looking?

Greetings
Wurstblinker

Wurstblinker wrote:

Where would you start looking?

First, towards logging (bzw. limitations), then suction pipe leaks, then valve timing / KW screw - especially since the pump is also slightly retarded (this doesn't necessarily mean anything, but it could . . .)

I have often had the engine running at very high RPMs recently, sometimes even reaching a stall.
Could my relatively new diesel filter have become clogged?
Could this potentially lead to a significant increase in consumption?
Even with a delicate accelerator pedal, the fuel consumption simply doesn't decrease!

I still hope that there is a completely simple and easily fixable reason.

Best regards

Good evening,
No calculation/measurement errors? Leaks? Fuel theft? Otherwise: Fill up to the bottom of the Sprite filling opening, drive, and refuel at the same pump. Taking it back would be an alternative!

lg robert

I can definitely rule it out.
Do you mean by 'rebuild' you mean putting the old chip back in, or?
However, I prefer not to work on the control unit again. It was completely nerve-wracking the first time to take it apart. Furthermore, the car is much more pleasant to drive with the chip.

Can anyone still say something about the diesel filter?

I still suspect that the high consumption is due to the new nozzles I installed!
Could there be a meaningful explanation?

Best regards

Definitely not the chip, he got it from me and I've been running it for about 70,000 km in the same engine with an average consumption of 5.5 to 6.5 liters.
But the nozzles could be the cause. Are they completely new? Is the spray pattern and opening pressure okay? He should also visibly cough more.

Good day, -it's actually a very sunny day here in Vienna +a bright blue sky.

Calculated fuel consumption on country roads and highways: 8.5l.

is calculated from the fuel injection amounts? after Vagcom?

Otherwise, more performance also means more fuel consumption. I can achieve an average of 165 km/h on the highway in a series-production (AGR broken) environment while consuming 8 liters of fuel. So, what's the problem? However, I also achieve a fuel consumption significantly below 5 liters in the summer, even when driving short distances away from the highway (approximately 15 km).
If the nozzles are the main components, it probably shouldn't be solely due to them, or are there some with a larger opening? Perhaps also incorrectly installed? I can't imagine having a diesel filter without a hole
How does fuel consumption in the city change when driving with an egg on the accelerator pedal?

lg robert