Measurement Data Block 1

Hello,

ich hab da mal eine Frage zu o.g. Measurements.
Okay, so I have a Golf III TDI 1.9 with engine code 1Z and approximately 210,000 kilometers on the odometer. It's now exhibiting the common issue of partial-load surging, and it jerks when accelerating slowly.
Okay, I've just read out measurement block 1 (using VAG-COM), and now I'd like to know if the values are allowed to fluctuate, or if they should ideally be as constant as possible. I think it's probably the latter.

My values are:

Speed:
fluctuates between 850 and 903 RPM.

Injection volume:
It fluctuates between 1.3 - 4 mg/H (I've read that it shouldn't be below 3 mg).

Voltage for sensor, control slide position:
fluctuates between 1.25 - 1.65 V.

Okay, so I think the injection timing is also "fluctuating" like that... but I can't confirm it because I only have the shareware version of VAG-COM.

Is this "fluctuation" in the values normal, or should I start looking for a new pump?

Thank you very much in advance, and best regards.
Hubert.

Hi Hubert,

You don't explicitly state it, but it's obvious that you measured it while the engine was idling?

The whole fun with the electronics in the TDI and the single injection system is a regulatory loop. It involves measuring, calculating, controlling, and then re-measuring, correcting again, and so on.

Fluctuations are therefore normal.

Please create a log showing the amount and duration of fuel injection fluctuations. Because a range of 1.3 to 4 seems quite high for idle.

Generally:
What do you hope to gain from measuring the idle speed if the tractor is jerking during acceleration? The typical "one-cylinder misfire" is far too "fast" for you to be able to detect anything about it at the interface.
If you're already considering getting a new pump, you could also try "operating" on the old one first – specifically, cleaning the flow control mechanism. How to do this is explained in technical articles.

If that goes wrong, you can always buy a new one .

m;

Hi Martin,

I was just at a friend's place who works at a VAG workshop. We hooked up the VAG-1551 diagnostic tool to my car and played around with the fuel injection quantity in adaptation channel 1. Originally, it was set to 128, and we changed it to 132 (we couldn't go any higher). Sure enough, the values in block 1 are no longer fluctuating as much, and the jerking has noticeably decreased. Maintaining 50 km/h in 4th gear is no longer a problem, but it's still there.

I suspect something went wrong during the last timing belt replacement, which was done about a year ago. That's also when the jerking started. However, this was done at a different authorized VAG workshop.
carried out... I don't want to make my friend look bad .

Can I check the basic timing belt settings? Perhaps there's something wrong with the belt tension or the tensioner pulley.

I'll definitely check the log sometime this weekend, and I'm curious to see what you think about the values!
I'm not that familiar with it... I did learn the automotive trade, but it was quite a while ago.

Greetings and have a nice weekend!

Hubert.

Quote:

I don't want to make my friend look bad, icon_smile.gif. Can I check the basic timing belt setting?

Ouch

That's exactly what you're doing with the question.
If you already had the tractor connected to the VAS, it would have been a simple matter to check the basic settings in block 000 .
But I'm sure he'll do it again.

It's highly unlikely that it's related to the ZR (presumably a component), because if it's rotating and properly tensioned (which the mechanism does automatically), it simply can't be the cause.

Sicherlich ist deine Pumpe einfach alt, und alte Maenner zittern halt ... Pumps as well.

Therefore: Perform maintenance, specifically clean the track switch mechanism.

m;