Afterglow: Is it Worth It?

Hello forum.

After successfully replacing the glow plugs on my G3 AHU, I'm now wondering how useful the afterglow function actually is.
Regarding running smoothness, I can't detect any differences compared to before (all 4 GK were defective in my case).
In my opinion, this also doesn't spare the engine, but it puts a significantly greater strain on the alternator (LIMA).
The only remaining effect is the exhaust emissions. However, will the fuel consumption increase, especially on short trips? My environmental conscience is directly proportional to the rising fuel prices, and besides, my alternator should last longer.

Can the afterglow be limited or disabled using VAG-COM?

Thank you for your responses.

HI,

I don't believe it's possible with VAGCOM.

But you can build the most basic electrical circuit. When the alternator is running and providing voltage (B+), you can simply disconnect the glow plug circuit (GSK) using a relay.

The circuit is analogous to the secondary battery charging circuit.
http://www.flying-wobs-trier.de/schrauberecke/elektronik/zweitbatterie.htm
(The guys copied the picture from an Austrian .

m;

Isn't there a nice spark when you simply switch it off? It's at least around 60 amps, right?
Best regards,

... and how are they otherwise turned on and off?

You shouldn't use a small electronic relay; it will likely overheat and fail.

m;

Hi,

It would be more sensible to simply interrupt the control signal to the glow relay, rather than the glow current itself. If that is being monitored, you could switch to a dummy relay or use an appropriate resistor. This is definitely simpler and safer than manipulating the glow circuit itself.

Even though it seems illogical (because, in my opinion, broken glow plugs shouldn't be prohibited either), this kind of action could cause the car to lose its operating permit (ABE) due to altered exhaust emissions in the first few minutes after starting.

It's also not really understandable why some only glow for a very short time, while the ALH/ASV can glow for up to 4 minutes.

To increase the consumption of glow plugs, afterglow is definitely useful... I think my glow plugs are probably not doing so well after 5 years and 83,000 km (I'll measure that sometime). Short trips are particularly hard on them, because if you have a 12-minute drive and afterglow for 4 minutes, that's a significant amount of time.

Best regards,

Jan.