No power while cold may indicate a problem with the Temp 2 sensor but usually this is indicative of a mechanical or fuel delivery problem. Injectors with poor delivery-spray patterns, excessive carbon deposits especially behind the intake valves or leaking valves, or an engine with compression problems leave their indications during cold-warming up performance. Since you have no history a Compression-leak down test is in order then check the injectors for spray pattern. 

Dennis
   

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of Miguel Pacheco
Sent: Saturday, April 06, 2013 6:34 AM
To: vanagon@GERRY.VANAGON.COM
Subject: Westy Gutless Until Warmed Up

I'm working on my friend's 86 Westy (2.1.) When she brought it to me, it would not get up to temp and was gutless. I could turn it off, then back on and it would run fine for a couple of minutes, then back to gutless. I installed a new thermostat and now it warms up and runs nicely once warm.
It's still gutless before it gets up to temp, though. Changed cap and rotor, plus new air filter as they were way overdue. Also, set TPS and this seems to be just right.
I'll hit the bible tomorrow and do some resistance checks, but any advice is greatly appreciated.
Thanks,
Miguel