[s-cars] Experience with leaking injectors?

[David Forgie]

Back in November, I decided to replace and reseal the injector inserts in the intake manifold due to signs of boost
leakage at the inserts.  I wrote this up about the project: http://forums.quattroworld.com/s4s6/msgs/266127.phtml

In the middle of that process, I sent the five RS2 green top injectors off for cleaning and refurbing (some parts,
e.g. pintle caps, O-rings, etc. were to be replace).  I got them back with a sheet showing that they all flowed very
close to the same and that they all flowed more than OE RS2 spec at 4 Bar (more is better?).

I honestly don't remember when it started but say since March, I have been having a hot re-start problem. Cold start was
fine but after driving somewhere, parking and then trying to restart, it would crank and crank and sometimes not fire.
I happened to find that if I opened the throttle a tad (take it off the idle switch and provide a bit more air) it would
catch and start, albeit with a stumble.

I investigated everything I could think of (including suggestions from qw folks)

1. Checked and cleaned the throttle body switch (checked out fine)
2. Checked and cleaned the MAF connector (checked out fine)
3. Checked and cleaned the G62 ECT sensor (checked out fine)
4. Checked and cleanded the G4 and G28 sensors. (looked good)
5. Replaced the G4 crank sensor (US$205 ouch).
6. Replaced the fuel pressure regulator
7. Replaced the fuel filter (actually that was probably one of the first things I did)

All of the above = no change in the hot restart situation.

Finally (?) I decided that I better look at the injectors so I pulled the fuel rail and put the injectors into 5 individual
jars while still attached to the fuel rail. I used my fuel pump testing harness ( http://forums.quattroworld.com/s4s6/msgs/260108.phtml )
to pressurize the fuel rail while I watched for leakage/spray from the injectors.  Then I let them sit in their jars for a
couple of hours.

By the time I checked again, No. 1 and No. 2 had dribbled more than a trace. No.1 more than No.2.  The other jars were dry.

I've contacted the injector guy and I will have to send him the injectors to retest.  His first question was whether the 
car had been sitting for long periods or daily driven. He suspects bad fuel.  I don't think so. It's not a daily but it gets
driven pretty much weekly or every 2nd week. 

Anyway, I was wondering what experiences with leaking Bosch injectors, either OE or RS2, that others might have encountered 
and what the solution is/was.

TIA

Dave F.