[Vwdiesel] starting TDI vs IDI

[FJ40Jim at aol.com]

Fwd message from Erik Lane <erikjlane at yahoo.com>
<< Actually on the newer tdi's the glow plugs aren't used
at all at temperatures above around 40F. that's when
the light just comes on for an instant and goes right
back out. at lower temps when the light actually stays
on for a few seconds or more is when the glow plugs
are really being energized.

i found that out after much work trying to diagnose
why the glow plug relay 'wasn't working' on a beetle.
everything looked normal, but put a light or meter to
the glow plug leads and there was no power, even tho
the light was coming on. i finally traced the problem
to a bad egr valve that was making it hard to start.
in my research i found that in order to make the
diesel as user friendly and similiar to a gas engine
they did away with the need to wait for the glow plug
light unless it's near freezing or below. i guess it
flashing on then off is just to let you know that the
light and relay are working, but aren't needed.

erik

--- FJ40Jim at aol.com wrote:
> Val,
> The TDI and other electronic diesels always take two
> turns of the crankshaft,(one turn of the camshaft
> position sensor) before the computer know where the
> engine is.  Then the computer turns on fuel.  If a
> mechanical ijection system is in good condition,
> then the engine will start in 180 degrees (or less)
> of crank movement.  TDI's don't start heating glow
> plugs when the interior light comes on, that's an
> old wives tale.  They start good because they are
> direct injected, fast glow with excellent fuel
> atomization due to high pressure & special nozzles.
> 
> Thanks,
> Jim Chenoweth
> Lancaster, Ohio, USA
> In a message dated 10/14/2004 11:35:53 AM Eastern
> Daylight Time, vwdiesel-request at vwfans.com writes:
> >From: "McCanless, James" <james.mccanless at lmco.com>
> >Subject: RE: [Vwdiesel] starting TDI vs IDI
> >To: Val Christian <val at swamps.roc.ny.us>,
> vwdiesel at vwfans.com
> >
> >I have had the TDI for 2 years and the Rabbit for 2
> months. The Rabbit
> >always starts quicker once the key is turned. The
> one thing you will
> >notice on a cold day is you will not have to wait
> as long for the TDI to
> >be ready. Reason? The glow plugs start heating when
> you open the drivers
> >door.
> >-----Original Message-----
> >From: Val Christian
> >Subject: [Vwdiesel] starting TDI vs IDI
> >I am just wondering if anyone can comment on IDI vs
> TDI starting. Right
> >now I have only one of each.  The IDI starts first
> tap of 
> >the starter.  The TDI always takes a turn or two.
>  I've checked the
> >usual (glow plugs, etc.) on the TDI.
> >Any comments from those experienced with both?