Join Date: Apr 2002
Location: Houston (Clearlake), TX
Use CIS pressure testing gauges. They're about $100 from Pelican or your local good auto parts store.
Sounds like your fuel pressure is too low. It would start easy but then run rich.
The WUR increases fuel pressure to lean the system as the engine warms up.
2014 Cayman S
2011 Cayenne Turbo
1979 930 (475 rwhp at 0.95 bar)