Is it bad to leave glow plugs on.

[Ian0391]

Hey guys, I have a 1.6td and the glow plugs are on those own circuit with a switch on the dash. I Stoll have the stock fuse before the buss bar though. Tonight I started my far and for some reason, the first time since I rewired them a year ago, I forgot to turn off the flow plugs. I was letting it warm up then when I got in 5 minutes later I realized they were left on. I feel so dumb for forgetting. So how much damage did I do?

[libbydiesel]

If you leave the glow plugs on they will burn out much more quickly.  Otherwise, no damage.  I would never install a toggle switch for glow plugs.  IMO you should use a momentary switch instead.

[sgnimj96]

you should use a momentary switch instead.

and make sure it has a relay that can handle all those amps (if it doesn't use the stock relay).

5 min is a long time for glow plugs to be on.      If you have to change them,   gear wrenches are worth it http://www.harborfreight.com/7-piece-metric-ratcheting-combo-wrench-set-95552.html
Removing the injector lines for the job is worth it, too.

[derf_kcire.XXII]

Not soo much damage done I reckon, but if you were to have a lame battery running the systems then it could of been an issue. The relay concept seem appropriate though, for the functionality of automated operation.

[burn_your_money]

If you have Bosch duraterms they are self regulating and you did no damage. Any other brand and you'll have to pull them to check.

[acidtonic]

If you have Bosch duraterms they are self regulating and you did no damage. Any other brand and you'll have to pull them to check.

This. I put duraterms in a car that had 4 bad plugs and a slow relay. Either way I had to get new plugs but since the duraterms are self-regulating they can be used in the 20-second relay and not burn out without switching to a fast system. All other plugs can't take 20 second relays and burn out quickly.

Also the newer cars run the plugs for  the first few minutes of operation to reduce smoke. So 5 minutes is not a big deal for a duraterm. Watch out for fakes though.

[TimpanogosSlim]

Momentary switch and the cheapest starter solenoid you can find

[rabbid79]

I have found that the most elegant, reliable, and affordable solution is to simply install a "Normally Closed" momentary push-button switch in series with the wire that goes to the head temperature sensor.  When the relay doesn't see a signal from this sensor, it defaults to coming on for something like 30 seconds.  So when you turn the ignition switch to the 'On' position, just hold the button down for however long you feel is necessary, and the glow plugs will come on during that time.  Otherwise, just leave the button alone and things will function 100% normally.

Granted, this isn't a solution if you're looking to leave the glow plugs on for an extended period of time, but it's especially useful for "lukewarm start" problems where the temp sensor thinks the glow plugs aren't necessary, but the engine isn't really warm enough to start without them.

[fatmobile]

Sometimes it's nice to have glowplugs run for awhile after the car starts.
 I heard the ecodiesels run for a couple minutes. Can anyone confirm this?
 Rabbid's method won't allow us to lengthen the afterglow.
 
 I just rigged up a stock glow plug relay to a push button so I could run it after starting.
 I used it to connect 12 volts to the red/black wire that comes from the starter (so the glow plugs are on while the starter is turning).
 I had to put a diode between the relay and the starter so the starter wouldn't turn when I pushed the glow plug button.

[vanbcguy]

I believe the Ecos do run their plugs longer. The AAZ cars definitely do, it helps reduce smoke during warm-up.

[RustyCaddy]

The early Rabbits have an afterglow circuit that runs for 5-10 seconds post ignition.  There is a short piece of wiring that gets connected to the loom to do this and not all looms have this piece.

[Dub_monster]

I set mine up on a momentary switch with a 70amp relay direct to the battery from what I found is they draw 60amps, so make sure you get a larger relay!