How To extend glow time with Vag-com - ALH

04colyZQ8 said:

Mmm I’m confused how do I set the ok temp of the glow plug time? Do you need to manually extend the glow plug time per degree of Celsius? I’d need a pot resister wired in the cts? And take several hrs to hot each coolant temp 5, 6, 7, 8c, etc.. and individually change them to 36700?

Click to expand...

Think of this as an offset. The ecu will determine glow time based on coolant temp sensor. You are just adjusting the adaptation value and increasing the glow time everywhere.

For example in the first post you can see see that at 7c the glow time is about 1 second, then after adaptation its 2.88 seconds. The glow plugs will not run very long at 7c but during a cold Canadian winter the glow plugs can run almost 10 seconds. The coolant temp you adjust the adaptation value doesn't really matter much, and you certainly don't need to adjust for each degree temp change. Just do the adaptation first thing in the morning after the car hasn't ran in several hours so that coolant is cold (not winter cold but just ambient).

Giberish33 said:

For example in the first post you can see see that at 7c the glow time is about 1 second, then after adaptation its 2.88 seconds. The glow plugs will not run very long at 7c but during a cold Canadian winter the glow plugs can run almost 10 seconds.

Click to expand...

Altitude has a massive effect on glow duration, on an 25* C day at 6,200 feet (my house) the glow plug light will stay on for 3 seconds or so, if I have some -35* C at 6,200' it seems the glow plug light is never going to turn off... I have a mk4 jetta, fwiw.

Does anyone know what the glow units here have to be for the glow plugs to actually come on? Is it any number higher than 0 or say any number greater than 1.00? I’m trying to set mine to only come on at a certain temperature.

Lots of good information on this topic in this forum. I recently bought VCDS for my 2014 Jetta TDI and can’t find instructions on how to program the glow plug time. Mine is different than the instructions I have seen so far. I have version 23.3 of VCDS if that helps. Anyone experiencing the same issues?

Kboger said:

Lots of good information on this topic in this forum. I recently bought VCDS for my 2014 Jetta TDI and can’t find instructions on how to program the glow plug time. Mine is different than the instructions I have seen so far. I have version 23.3 of VCDS if that helps. Anyone experiencing the same issues?

Click to expand...

Go to Ross-Tech's website. there, you will find about all you need to know about what you can do with your VCDS.

mStrad said:

Does anyone know what the glow units here have to be for the glow plugs to actually come on? Is it any number higher than 0 or say any number greater than 1.00? I’m trying to set mine to only come on at a certain temperature.

Click to expand...

I can only suggest that you wait until that certain temperature you wish to use is the temperature, then try different off-set values until you discover the off-set that activates the pre-start glow operation at that desired temperature.
Or, cobble up a variable resistant coolant sender as a temporary substitute, monitor the ECU value of temperature from that adjustable sender, dial in the temperature you want, then try different off-sets.