Octavia Starting Problems (AGR Engine)

Hello community,


"I've been experiencing a starting problem with my Octavia for some time now. (Engine code: AGR, 85,000 km)"
At the beginning of August, the timing belt was replaced, and shortly after that, the problems started.
When starting, it usually jerks twice briefly at around 400 RPM, then it shuts off again.
On the second attempt, there's a brief jerk, followed by a momentary spike in the RPM to 1,500.
then adjusted to normal idle values. The colder and more humid the weather, the more pronounced this effect becomes.
That is the behavior.
It starts perfectly when the engine is warm. However, it's probably something else if you suspect a glow plug issue.
It's still too warm outside. What bothers me most is the timing, so close to the timing belt replacement.
LMM is relatively new!
AGR is deactivated via the hose, but I can't explain how that could be related.
Acceleration and top speed are good!
My own considerations yielded the following results:
Either the belt was misaligned during installation, or the injection start time is incorrectly set.
Or maybe it's the battery?
Has anyone had similar experiences, or can someone confirm or refute my thoughts?
Unfortunately, I don't have a VAG-COM, and I don't know anyone who does. (I'm from Hof; perhaps Rainer K. could help? )

Thank you very much.

Matze.

It is highly likely that the start date of the funding is incorrect.
I had almost the same problem with my AFN.

Matze22 wrote:

At the beginning of August, the timing belt was replaced, and shortly after, the problems began. When starting, it usually jerks twice briefly at around 400 RPM, then it shuts off again. On the second attempt, there's a brief jerk, followed by a momentary spike in the RPM to 1,500, before it settles down to normal idle values. When the engine is warm, it starts perfectly. Acceleration and top speed are good! My own considerations yielded the following results: Either the belt was misaligned during installation, or the injection start time is incorrectly set. Or maybe the battery?

"It's probably not the battery; based on general experience, battery issues usually manifest first during a warm start."

Therefore, I also suspect the motor control unit/ESP.

NW can be measured directly using a setting gauge -> search function.

You can also roughly estimate the position of the ESP using a multimeter -> See the technical article on pump adjustment.

I would also not completely rule out a loose crown wheel gear.

Quote:

Timing belt replaced, shortly after the trouble

began.
... for example, if the sprocket was unnecessarily loosened and then incorrectly reassembled.
Other errors during a ZR change should actually become apparent immediately...

ohh, for someone with two left hands, trying to measure something themselves is probably an insurmountable obstacle . I can actually follow the theoretical explanations/technical articles here quite well, but I would never try to do it myself in practice, because absolutely everything would break.

My main concern is to give my mechanic some specific "tips" because otherwise the car will be stuck in the workshop for another three days, and in the end, they'll probably diagnose another faulty turbo!

Was ist das ausgeleierte Zwischengetriebe? Wasn't that more of a 1Z problem? Or does it also occur in later model series?
I wouldn't be surprised if the guys forgot to tighten something properly. That would also explain why it's gradually getting worse.


I scheduled an appointment at the workshop on Thursday, and I'm curious to see what the guys at "Flotten Schraubenschlüssel" have to say! I do have a warranty on the repair, right?

Matze22 wrote:

Wasn't the worn-out K-ring gear more of a 1Z problem?!?

Okay, I understand. Please provide the text you would like me to translate from German to English.

Quote:

Or does it also occur in the later model series?

Yes, but most likely...

Quote:

if the guys had forgotten to tighten something properly. that would also explain why it's slowly getting worse.

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I signed up at the workshop on Thursday, and I'm curious to see what the guys from "flotten schraubenschlüssel" have to say!

Should I guess?
Anything is possible, but never admitting to any potential mistake of their own.
If necessary, the killer argument "that was already the case" will be used - and what will you counter that with ?

First of all, thank you to everyone who responded!

I'm curious to see what comes out of the workshop tomorrow...
I also suspect that they will try to distance themselves from the situation. I started this thread to have some arguments against them, so let's see who comes out on top in this verbal battle .


"By the way, I noticed yesterday that it's emitting a lot of white smoke from the exhaust when starting. So, it's definitely the K-W (kickstarter) gear, right? And is there any way I can check it myself, given my limited skills?"

Hello everyone,

To briefly clarify the situation:

Yesterday, I had an appointment with the doctor, and I explained the problem to him just as I described it above.
Of course, I kept my theoretical solution to myself. After the master mechanic drove the car into the garage, it took less than 2 minutes for him to return, and the following dialogue ensued:

Mechanic: Have you been to another workshop about this problem before?
me: no, why?
m: Her EGR valve is disconnected!
me: Yes, I know, I did it myself!
m: (with an even angrier expression) "So, now we know why it's starting so poorly, and it also has a fault in the control unit!"
Okay, but I've been driving like this for a while now, and everything was fine before the timing belt was changed. However, if he can explain to me what the EGR valve has to do with the starting problem, I'm willing to reconnect it.
m: Well, every component is good for something!
me: hmm, I didn't really want to know that precisely.

Anyway, he eventually gave up and, after 1.5 hours (!!!), he came back looking embarrassed and announced that, miraculously, the fuel injection pump was misadjusted, and that they had fixed it!
I asked him if something like that could happen during a timing belt replacement (just to see what he would say).
He said that something like that had never happened before, and he couldn't explain it because the pump is connected with a thorn (aha!).
Anyway, it had been fixed again, and sure enough, it started working again!
Let's see if this is a lasting fix; I still fear that the gearbox mainshaft gear might be loose.

"Regarding the topic: 'How can I make a customer as stupid as possible?'"

Sad!

Matze.

Matze22 wrote:

Anyway, he tried again, and after 1.5 (!!!) hours, he came back, embarrassed, and announced that the fuel injection pump was (oh, wonderful) misadjusted, and that they had fixed it! I asked him if something like that could happen during a timing belt replacement (just to see what he would say). he: something like that has never happened before, and he can't explain it because the pump is connected with a thorn (aha!)

.
...and that's why it will always, without exception, be done meticulously -> forgetting or being careless is simply impossible, of course!

Quote:

regarding this topic: "how can I make a customer as stupid as possible"

Sad! ... but unfortunately, it's a common occurrence in workshops.

As soon as the starting behavior gets worse again, I will contact them again and make sure they address the issue.
I suppose they only adjusted the pump, but not the NW (presumably referring to a specific component or setting).
-> If the crankshaft sprocket were to loosen further, to the point where the engine starts poorly again, then the valves and pistons would be even closer to colliding, and eventually, something would really break .