[Vwdiesel] Glowplugs how mine works -- ( Slow and fast )

[H.Hagar]

First the old slow system  :   The light on dash does not tell status of plugs.
it is a timing indicator showing amount of preheat suggested. Plugs can be
heating , even with light off.   Plugs stop heating the minute engine fires, regardless of
temperature.(likely  controlled by alternator) .  Knowing this you can find out what system
you have in your VW. With engine cold turn key on but do not start. With a testlight connected
to plug buss, time the interval from dashlight goes out , to test light goes out.
It will be in the order of 15 to 30 seconds. Then do a start and see if testlight goes out
when engine fires.     IF so  you have the old "Relay" installed.     If  test light
stays on after a startup "afterglow"  you have the new "Relay" installed.                   

The turbo I have with afterglow does not have the dashlight working so I can't test that,
however I do have a light connected to plug buss  and the afterglow is working.                 Hagar

PS :   This to help Wade York.