Glow plugs indicator light

[A Guy]

Why would the indicator light for the g-plugs come on just after the car has started?  It is not as bright as when they are heating - pre starting. It actually flickers a bit and then stays lit.  Loose wire - a bad plug...?  The car starts well.  Any suggesting of where to start are greatly appreciated.
Out.
Greg
Happy St.Patty's Day!!!!!!!!!!!!!!!!!!  

[HP]

With my car happens the just same, but instead of the glow plug LED, it's the battery LED. Stays on for brief seconds after the engine gets started. Then the idle lows down a bit as the light fades!
In my case, I suppose the battery is aiding the engine for its firt revs ( :idea:  ...). I've been told it's normal. Is it?!
In your case, possibly a worn out plug!  :?  Don't know..

[wyldman]

You should not see the glow plug light after it starts.

Either the glow plug relay is bad,or you have a faulty ignition switch.

[stewardc]

What car do you have. On A2 and A3 cars, that is a sign of water in the water separator (there's a sensor in there).

[A Guy]

I should have stated that sorry :oops:
I have a 91 Golf w/1.6L N/A
Where is the water separator?
Thanks
Greg

[wyldman]

There is a water trap under the car,in front of the tank.There also may be one in the bottom of your fuel filter.

[stewardc]

The water sensor is in the one under the car.

[hillfolk'r]

if your glow plug light is flashing after startup,drain seperator under car,,if batt light is on,just blip the throttle a little,,its an exitation thing,and its normal,and yes,the idle will drop when the batt lamp goes out ,because now the alternator is now working to  charge up the batt,after firing the car up,glowing,etc,,,,if you have a reallazy one,like i do,,and you bring up the revs  very slowly,when the alt. finally kicks in,you will hear the load change affect the rpms,,,,,,basically its like one of those "1 wire gm alternator",that  the domestic guys use,,let them choke on diesel smog and drain that seperator,even if the light isnt on!!!im thinkin about retrofitting one of those water seperator assemblies on my 79

[twopeanuts]

I've got an 82 Rabbit Diesel L - for exactly a week today (and love it).

Anyway - question - the first few days I had the car, whenever starting it cold, the glow plug light would come on solid for a sec or two then flash (with a fairly loud click click click click) that seemed in time with the light flashing - then the light and clickin would stop - and I'd turn it over with the throttle about 50% and it cranks first try even with iced over windows in the morning.

So I was suprised ~Wed morning when I got in and the sequence changed, the light was solid, then flashing, then off but no clicking sounds - silent - so I thought something had failed -  turned it over and it cranked anyway (and on a cold morning).  

It stayed silent like that until I went to lunch today - and now it is back to clicking with the glow plug light flashing.

Warm starts - no light - no clicking.

So what is normal?  Silent or Clicky glow plug period?  

Thanks!

[hillfolk'r]

try wigglin the relayaround,,sounds like a bad connection,,it should come on for a while steady,,no blinking stuff,,,or maybe a bad relay,,try slightly twisting or pushing on the relay,,ive had bad connections occur in the fusebox area from dampness/moisture,,ihad one that ihad to pull the relay out slightly for it to workcorrectly,,a cruddy connection where the relayplugged in,,probably one of those 2 things,,sounds like semp sensing side is working,,,,,

[HP]

And what about,

With my car happens the just same, but instead of the glow plug LED, it's the battery LED. Stays on for brief seconds after the engine gets started. Then the idle lows down a bit as the light fades!
In my case, I suppose the battery is aiding the engine for its firt revs ( :idea:  ...). I've been told it's normal. Is it?!

 :|   :?:

[hillfolk'r]

yea thats normal,,,,,,gotta blipthe throttle for lamptogo out,,,alternator may need some revs to "exite",,the speed drop you hear when the lampgoes out is the alternator kicking in to charge,remember,you just glowed,then started,,thats some juice used from the battery,gotta put it back,,,,,totally normal,,,,,

[HP]

Just wanted to know the actual reason for that. Thanks.

[hillfolk'r]

hmmm, i suppose i could break out my book on generators+see the cause on it,,generator/alternator,same thing in my world,zap ,basically,,,did you want a "basic electrical" type explination/theory???not to toot horns+stuff,but all the "old" guys in the shop pass all the elec. problems to me,computer diagnostics,or even when a light wont work,heehee,and i do know an electrical engineer that does failure analysis on computer chips too,worked for ibm,theres lotsa knowledge out there waiting to be "picked up!",,

[Asymtave]

I've read that the alternator doesn't "excite" at lower RPM's during starting to ease the load on the starter.  So, when you're cranking, the alternator is just along for the ride putting very little load on the starter.  

Then - once RPM's get above a certain point (1200 RPM?) the alternator knows the motor is running, excites and starts putting out current. This is when the "ALT" light goes out.   Makes sense to me.  Clever Germans!