Polo 6N1 AEE 1.6L engine bay oil leak/contamination

Today, I had to unfortunately discover that the entire engine compartment is covered in oil . The oil stains are mainly located on the passenger side, near the axle components, and on the underside of the hood, next to the air filter box on the driver's side.

The dipstick showed no oil. Strangely, the oil pressure warning light turns off after the engine is started. The engine doesn't make any unusual noises. My suspicion is that the crankcase ventilation system is blocked. Therefore, I first removed the air filter housing. Inside, there is a clear oil emulsion. I haven't investigated any further yet. I couldn't find any leaks or defects anywhere.

Where does the oil come from?

Good evening.

If I'm not mistaken, your engine still has a non-heated crankcase ventilation system installed. TN 036 103 464 G)

Condensation and oil sludge accumulate in these areas, which then freezes in the winter, causing the engine compartment to look like you described.

After the exchange, the world should be back to normal.

Polo and Golf IV models are more frequently affected by this issue.

If you're willing to invest a lot of love and time, you can check out the Poloforum, where you'll find instructions on how to retrofit a heated version.


Waved.

The crankcase ventilation system on this engine is not heated.

Where did the oil come from? It didn't come from the dipstick, as is often reported. What could be broken right now?

Good morning.

Typically, it either leaks oil from the seal on the plastic housing, or the housing develops a crack.

If the pressure is escaping through the oil filler cap, the engine bay wouldn't look like what you're describing.

Of course, it's conceivable that the pressure from the KW also forced some of the poetry out of you, but I find that even less likely.

verschandeln the engine and take it for a short drive, and you'll quickly see where the pressure is escaping from.


Michael.

I continued working on it today.

First, I cleaned the most affected parts roughly with brake cleaner. Then, I removed the KGE (cylinder head gasket) and cleaned it as well with brake cleaner. The housing doesn't appear to be cracked. Then, my neighbor and I checked the compression using a compression gauge. Measured from the direction of the belt drive, the cylinders have the following compression values when the engine is cold:

14.7 bar
15.5 bar
14.8 bar
15 bar.

However, I don't trust the readings from the testing device because I think the values are too high. The spark plugs also look good and all show a consistent wear pattern. After cleaning the air filter housing, reassembling everything, and topping up the oil, I carefully took it for a test drive.

The engine is behaving normally, and I couldn't detect any major leaks. When it gets a bit warmer, I'll thoroughly verschandeln the engine of any oil residue, and until then, I'll carefully monitor the oil level. However, given its mileage of approximately 385,555 km, it's bound to burn some oil.

Tip: After the initial cleaning, dust the suspected areas with flour! Even the smallest leak reveals itself with millimeter precision.

Otherwise, oil has the property of seeping everywhere. The airflow, or the mini-hurricane generated by the radiator fan, also distributes it.

The AEE isn't a "frost motor," was that the 1.4L engine with 55 kW (AHW, AXP, etc.)?
I had the AEE (presumably referring to an engine component or system) in my Octavia 1U, and it functioned perfectly until I sold the car with 277,000 km (approximately 172,000 miles) on the odometer (without any oil consumption between oil changes).
The compression values are quite consistent (with a maximum difference of only 0.5 bar), which means the engine should still be able to function for a long time.

The AEE in the Polo has an unheated EGR system and is therefore a potential candidate. Possibly, the coolant expansion tank in your Octavia was heated.