PostPolo Verbraucht viel und ruckelt | Posts 16+

Let's move away from heating oil for a moment... Back to the question. I don't have a crystal ball, but my guess is that the air bubbles are rising from the pump into the line. Let's check it out! The shaft seal might be worn or damaged.

Best regards!

So, the stain under the car was actually motor oil mixed with rainwater. It's due to a faulty oil pressure sensor (is that the technical term?).
I also thought about the possibility of a leak in the ESP system, but how could something get into the fuel line before the ESP (while the engine is running)?
What is the function of the white plastic part that sits on top of the fuel filter and through which the return hose runs? Is it an automatic air vent for the filter? Does it contain a type of check valve to allow air out but prevent air from entering?
From below, the vehicle is verschandeln and dry along the fuel lines.
Regarding the cold start accelerator, where can I find any tips on adjusting the ESP (Electronic Spark Advance)? The screws indicate that someone has likely tampered with the settings before.

And one more thing, although it's a post-polo car, it's still in very good condition and, in my opinion, hasn't been abused. It also doesn't have any dents or scratches. The performance is fully there . It starts up really well too. So I'm not worried about the engine itself. A 1.9L engine with 64 'killer' horsepower shouldn't be easily damaged.

Best regards,

If you're serious about using heating oil, there's nothing more I can do to help you. If you genuinely don't know that using it in vehicles is a punishable offense, let me tell you that even if you fill up with regular diesel now, the presence of heating oil can still be detected for a very long time.

1.9 SD with 64 horsepower!
I can't believe it. They're selling this engine in new cars in Argentina. Before, they always had the 90 hp VP-TDIs. Those didn't sell well (or the workshops couldn't handle them), and then VW dug up this old 1.9 SD engine. I honestly didn't think they would dare to sell that ancient thing. I thought it was more likely a special, "new" low-maintenance design for Latin America.

Well, you never stop learning...

Regards,

Olaf.

Andi84 wrote:

What is the function of the white plastic part that sits on top of the fuel filter and through which the return hose passes?

This plastic part is used to regulate the temperature of the return fuel line. Up to a certain temperature, the return fuel (warm diesel) flows into the filter and is then immediately made available to the pump again. Above a certain temperature, the fuel flows directly back into the tank.
By the way, there have already been cases where this part has broken due to aging, causing air to enter the fuel injection system. The problems were probably similar to what you're experiencing.

Hey, thank you very much, Bertil!
Yesterday, I took the part off and tried blowing through it with my mouth to see if there was a valve inside. At a certain pressure, something suddenly shot out from the other end, and it became easier. Unfortunately, it's still shaking this morning. I'm going to buy a new one tomorrow. That would also explain why it only shakes when the engine is cold.
Sure, here is the translation of the text from German to English:

'MFG' stands for 'Mit freundlichen Grüßen,' which translates to 'Sincerely' or 'Best regards' in English. It is a common way to end a formal letter or email.