LMM Cleaning: The Problem and Solution

Hello everyone!

Unfortunately, I don't have a way to diagnose the issue with my car, and I don't know anyone with the same or a similar model, so I can only make (more or less) subjective judgments about whether my car (Golf TDI / AJM / approximately 60,000 km) is running well or consuming a lot of fuel.

Having come to the conclusion that 7 liters (according to the MFA) is definitely too much fuel consumption, especially considering the very weak performance (as I said, subjectively), and after reading all the relevant threads, I decided to clean the mass airflow sensor (MAF).

However, I don't really have much experience cleaning LMMs, and I've now read different opinions: Some say to spray them with Bremen cleaner, others suggest using a cleaning bath, while others claim that 'the sensors are too clogged for cleaning to help,' or that 'no dirt can get in there, so cleaning is pointless.'

I hope that someone among you (perhaps even with the same engine as I have) has already had experience cleaning the mass airflow sensor (MAF) and can help me. Or maybe someone can suggest an alternative cause, or tell me that investing in a new MAF sensor is unavoidable.

I am already looking forward to reading your answers .

Stefan.

Hi!
How old is your car?
Do you know that VW now offers a warranty of up to 4 years on mass airflow sensors?

Thorsten.

Hi,

My car is only 3 years old and has 60,000 km (approximately 37,000 miles) on it. Today, I'm taking it to the dealership.

I will definitely write down what he has to say about the consumption.

Greetings.

Hi Steve_Wonder,

mach doch mal den Durchzugs-Test vom Ulf. Then you have...
Could you give me a rough estimate of how well your car is performing?

Regards,
arne

I also have the AJM engine, and after using VAG-COM, I detected a problem with the mass airflow sensor.
I disassembled the component, cleaned it in an alcohol bath, and drilled a small hole for airflow adjustment (see technical articles/tips).
The result was a noticeably smoother and more consistent power delivery.
However, in my opinion, nothing has changed regarding fuel consumption.

Hello Stefan!

The faulty mass airflow sensor (MAF) only resulted in reduced power in my car. During acceleration, the power would fluctuate by about 10-20%. The engine would initially start with a certain amount of power, only to reduce it shortly after. After a few seconds, the power would sometimes increase again. All of this could be observed on the instantaneous fuel consumption display of the multi-function display (MFA). With a properly functioning MAF sensor, I get a value between 13 and 14 liters per 100 km at full throttle in 5th gear. With a defective MAF sensor, the value fluctuated between 10.7 and 12.5 liters per 100 km.

I haven't observed any increased fuel consumption.

Good luck with troubleshooting!

Regards,
mcgregg