CIS is pretty robust.  Works great up until you get junk past the filter and
into the system.
The control pressure regulator clogs, injectors start spraying weird
patterns, and God help you if the fuel distributor fouls.
Then you have things like the accumulator that leak fuel underneath the
vehicle and those #@$%& copper crush washers everywhere, pretty much
one-time use only.
However the CIS fuel pumps hold up well; I had a 22 yr old Scirocco with the
original.

If you ever look closely at a CIS system you can really appreciate the
precision machine work and quality of materials.  The airflow housing is a
beautiful thing with glassy smooth pivot bearings, machined aluminum funnel
and anodized counter weight.  The fuel distributor flow orifices are laser
cut and the plunger is such a precise fit that pressurized fuel doesn't leak
out even with no rubber seals or o-rings.

CIS is kinda like the last steam powered locomotives- brilliant masterpieces
of mechanical ingenuity, though hopelessly complex and cumbersome.

Some would argue modern EFI is hopelessly complex, but not from a mechanical
point of view.  And with OBD, a simple scan will find most problems and let
you know about it in plain English.
Diagnosing CIS problems OTOH takes a little skill.

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
neil n
Sent: Monday, November 16, 2009 4:40 PM
To: vanagon@GERRY.VANAGON.COM
I can't help but wonder if CIS hasn't gotten a poorly deserved bad rap
over the years. To me it seems like a simple system (CIS, not CIS-E)
that would be quite reliable. Mind you, a rebuilt fuel distributor
looks pricey, (are they even available new?) but I bet it takes quite
a few miles before that part fails. And if one keeps an eye on those
high pressure fuel lines, why not keep it?

Neil.

--
Neil Nicholson '81 VanaJetta 2.0 "Jaco"

http://tubaneil.googlepages.com/

http://groups.google.com/group/vanagons-with-vw-inline-4-cylinder-gas-engine
s