SDI AKU: Engine Misfires After Start, Power Loss

Hi!

We have a Seat Arosa SDI with engine code AKU, 163,500 km, manufactured in 1998. Until 3 weeks ago, it was running great, everything was original, but the AGR valve was defective. I often pushed it pretty hard on the highway.

Seit 3 Wochen ist die Leistung weg über das ganze Drehmomentband. Es ist, als ob man einen Anschlag unter das Gaspedal gebaut hätte, der maximal Halbgas zuläßt. Bei Motorgeräusch, Abgastrübung und Verbrauch gibt es keine Auffälligkeiten. Auf der AB ist nur Tempo 120 drin, mit Rückenwind 140. Die Glühkontrolle blinkt nicht, es wird also kein offensichtlicher Notlauf angezeigt. Beschleunigungswerte wie ein 40-Tonner. Das isThat's corrosive!

It all started with the engine running for a few seconds after starting with a slightly elevated idle speed (1300 RPM) and producing a lot of smoke. This behavior occurs sporadically, and it also happened before the first instance of the power loss. Sometimes, however, the opposite effect occurs: after starting, the engine runs briefly at a too-low RPM and then recovers.

Unfortunately, I'm a bit lost here. Perhaps the fuel quantity gauge has become stiff after 100,000 km of operation with biodiesel and gasoline. What particularly interests me is: Are there any types of emergency operation that are not indicated by the glow plug light flashing? Does the engine control unit (AKU) even go into emergency operation mode if the fuel quantity gauge is stiff or stuck? Or are there other plausible explanations?

If the fuel filter was clogged, it usually presented with completely different symptoms: hesitation or jerking when accelerating at full throttle, starting around 2500 RPM.

If anyone near me (in the Stuttgart area) has a VAG-COM, that would be great.

Best regards,
Holger.

SeatArosa1.7SDI wrote:

... Perhaps the quantity indicator has become stiff after 100,000 km of operation using renewable methane and petroleum.

Difficult to operate... or simply broken.

SeatArosa1.7SDI wrote:

What particularly interests me is: Are there any types of emergency situations that are not indicated by the flashing of the preheating lamp?

No, at least not from STG.

SeatArosa1.7SDI wrote:

Does an AKU (Automatic Route Control) actually switch to emergency mode in the case of a difficult or jammed pointwork system?

"Why not? You should normally receive a standard adjustment. But that's not always the case."

SeatArosa1.7SDI wrote:

Or are there any other plausible explanations?

Please provide the text you would like me to translate from German to English. I will then provide the translation.
If the leakage losses in your pump become so significant that the pressure ratios are disrupted, anything can happen. However, you don't necessarily have to receive an error message (as seen with many jerky variable pumps).

I simply assume that the pump is completely worn out and has reached the end of its lifespan.

Did you not previously report problems with this pump?


EDIT:
I'm sorry, but I cannot access external websites or specific files online. Therefore, I am unable to translate the text from the provided URL.
That might be helpful to you...

Hi! Thanks for the tips and the link. Broken fins in the HD unit - well, that's just what I needed. Clogged filters sound much less serious.

I was just thinking about getting a new car. I would definitely want a gasoline engine with LPG (for me, the era of direct injection is over due to political restrictions and the diesel particulate filter). I've done a little research. Lada offers LPG as a factory option at the lowest price, but I'm not willing to pay the €2200 surcharge for LPG (and that's without LPI technology), especially considering the extremely unattractive cars and the generally high fuel consumption. A 98-octane optimized 1.2L naturally aspirated engine would be more appealing to me.

Okay, I'll keep my AKU for now! It can still reach speeds of up to 150 km/h on the way home from work, especially when going downhill. Of course, its performance is on par with a cargo vehicle, but it's still good enough for getting around.

My plan is as follows: The third timing belt was installed at 140,000 km. I'm currently at 164,200 km. If the weak pump can last until 200,000 km, I can combine the pump and timing belt replacement at the same time. It should be doable with a used pump for under €1000. The question is whether the injectors should also be replaced at this mileage.



Didn't you already report problems with this pump before?

Yes. It's been exactly 3 years now. Let's see if I can get out of this situation as easily and cheaply this time https://community.dieselschrauber.org/en/viewtopic.php?t=5866&highlight=sporadisch+starkes+nageln.

'By the way, what would happen if the pistons in the rotary vane pump are stuck? Would a diesel flush from Liqui Moly help? I could buy a can of that. It's just a bit awkward to connect.'

I once had a link from a Bosch website where you could find the part numbers for fuel injection pumps. Can anyone help me find it?

Best regards,
Holger.

SeatArosa1.7SDI wrote:

... I was just thinking about getting a new car. If I were to buy a new car, it would definitely have a gasoline engine with LPG (liquefied petroleum gas) as the fuel.

... Good idea ...

Quote:

"By the way, what would happen if the pistons in the rotary vane pump are stuck? Would a diesel flush from Liqui Moly help? I could buy a can of that. It's just a bit awkward to connect."

"Stuck FZP? Nah, I don't think so. More likely corroded. RME is the world champion in that area."

Quote:

I once had a link from a Bosch website where you could find the part numbers for fuel injection pumps. Can anyone help me find it again?

You should be able to find it under the links.

/links.php

Here you will find the abbreviation.
http://ecat-online.bosch.de/toc/frame1.html

If I were to buy a new car, it would definitely have a gasoline engine with LPG as the fuel type...

... Good idea ...

...but I couldn't find any vehicle on the market that came close to my ideal specifications: a 1.2L naturally aspirated engine, optimized for 98 or 100 octane fuel, with a flexible-fuel (FFV) engine control unit (allowing for any ethanol blend) + LPG with an LPI system. It would be a tri-fuel vehicle.

I'll keep my AKU for now, and I'm going to really fine-tune everything so that my penalty tax is worth it!

Glued FZP? No, I don't think so. More likely corroded. RME is the world champion in that area.

It might be. However, considering the mileage of 163,500 km or the age of 8 years, blaming RME as the sole cause seems a bit unfair...

Here you will find the abbreviation:
http://ecat-online.bosch.de/toc/frame1.html

Excellent catalog . Just: Where are the prices listed ?

Regards,
Holger.

Unbelievable! The original performance has been back for over a week! In the meantime, I filled up at my usual gas station with RME, and some time later, the performance returned! Could it be that I just got a bad batch of fuel? Or is this a case of spontaneous self-healing? Or perhaps the pistons of the rotary vane pump were stuck due to an air bubble and then came loose again due to the dry RME?

Naja, ich werd es wohl nie erfahren. Things you see...

Now, we're heading straight towards 200,000 km...