Just a wild guess, but maybe your cat is starting to restrict exhaust airflow??

DM&FS

At 12:18 AM 11/15/2011, greentabe-vanagon@yahoo.com wrote:
>It's easier to post than go outside and actually work on this --
>it's expected to get close to freezing tonight!  (I know, some of
>you are laughing at me)  I haven't fully finished troubleshooting,
>but here goes anyway: My relatively new-to-me stock 2.1 has trouble
>starting when cold but runs fine when warmed up.  I usually crank
>for 5-10 seconds, stop, and do it again.  I might have to do this 3
>or 4 times before it actually starts.  When it does eventually
>start, it runs sort of OK for a few seconds, then slowly starts to
>miss more and more until it conks out.  Rinse and repeat.  I'm
>pretty familiar with how the Digifant FI is supposed to work and
>have checked the temperature 2 sensor and idle control systems,
>which appear to operate normally.  Idle switch clicks but I haven't
>checked for continuity yet.   So what I see is that the FI gives an
>extra squirt of fuel for a bit, which eventually allows the engine
>to start once enough unburnt fuel is present, and as that fuel burns
>off and the FI leans the mixture, the engine dies.  Adding some
>quick start helps. Once warmed for a minute or so, the engine runs
>fine at idle but dies under throttle until fully warm.
>Suggestions?  How come the FI is not enriching the mixture
>enough?  Something else going on? tabe johnson_90MV