I have never seen this type of failure.  Usually the Fuel pressure
regulators fail by either making the fuel pressure super high (runs
really rich) or the diaphragm inside goes bad and allows metered fuel to
get sucked into the vacuum line that leads to the intake.  Either of
these is a rich scenario.

Cold start issues are usually either Temp II, valve adjustment, or idle
stabilization problems.

Just my experience.

--
Thanks,
Ken Wilford
John 3:16
www.vanagain.com
Phone: 856-327-4936
Fax: 856-327-2242

On 12/22/2010 9:47 AM, Mike S wrote:
> At 10:02 PM 12/21/2010, Scott Daniel - Turbovans wrote...
>
>> The fp regulator isn't senstive to temperature ...
>>  I havn't seen an fp regulator that was bad cold, but fine hot.
>
> Cold engines need richer mixtures than warm engines. If the FPR is
> leaking (pressure too low), the resulting mixture may be to lean to
> start/run cold, but seem fine when warm.
>