Re: [T3] Build date of my 1969 Fastback ? Thanks

[Greg Merritt <gregm@vwtype3.org>]

<x-flowed>At 4:41 PM -0700 4/18/03, Edward Morris wrote:
> Hi Greg-
>
> I'm VERY new to air-cooled VWs (< 3 weeks) but I'm
> getting a unsettling insight as to why so many abandon
> the FI puzzle.

	Nah, it just takes a while to get up to speed with the 
particulars, especially if you "grew up" on carburetors.

	What *really* gets people frustrated is when they start 
buying replacement parts they don't need (or don't belong on their 
car, heehee) and feel like they're throwing good money after bad.  A 
neat thing about the injection system is that so many of the 
components are separately testable and you can rule them in or out 
relatively quickly.


> Your response states that the cold-start system was an
> "add-in" (meaning: option?) for pre 1970 Type 3s.   I

	Yeah, VW didn't make this a standard part of the system until 
the 1970 model year.  There was an optional system available for 1968 
and 1969 cars.  (Russ, was this a retrofit for the older cars, or did 
it first appear in like '68 or '69?)

	The optional cold start valve mounted on the front plate 
(front is front) of the intake air distributor.  When it became 
standard equipment, it got its own proper place down low on the right 
side of the IAD.  (Well, at least for '70 and '71; not sure about '72 
& '73.)

> One thing that I DO know - my car is very hard to
> restart once its been warmed up.  I thought I read of
> others on the type3.org list who had similar problems.
>  They were invariably pointed to the "cold start" as
> the likely suspect.

	I think it's popular to blame the CSV, but it really gets 
much more of a bad rap than it deserves.

	Note that it only operates when the starter is turning over 
*and* when its temperature sensor is below about 50F or so (from 
memory).  A common misconception is that it's designed to run as a 
cold engine warms up, like a choke, but this is wrong.  You know when 
you hit the gas pedal once or twice on a cold carbed car to squirt 
some raw gas into the manifold via the accelerator pump on a cold 
morning?  Well, *that's* what the cold start valve does.

	The actual "choking" function in D-Jetronic is handled by the 
ecu when the cyl &/or intake air temp sensors tell it that conditions 
are cold.  The ecu just lets the injectors squirt for a little longer 
each cycle.  And while I'm at it... the acceleration-time accelerator 
pump function is handled by the ecu when it gets a signal that you've 
floored it; relevant sensor depends on the year.

	The CSVs can leak, in which case the car will always run 
rich.  Other problems can occur if they've been miswired, as has been 
discussed here in the last couple of days.

	The consensus is that the '68 and '69 cars really don't need 
the CSV.  I know my '69 regularly started just fine in temps below 
10F.

	Edward, post more info about your troubles here.  I'm sure 
you'll be able to figure out the trouble.

Regards,
-Greg
'69 Squareback

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