Try cycling the ignition on the fly. If it clears you have an O2 sensor or circuit problem. Start with the ground wire in the harness to the distributor. That is the important one. Full throttle will cause the O2 sensor to be ignored if the throttle switch actually works.

Dennis 

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of Kevin Duvernay
Sent: Friday, February 27, 2015 5:11 PM
To: vanagon@GERRY.VANAGON.COM
Subject: 87 2.1 dies after 30 seconds

All,

Trying to help a buddy out with a strange issue. His 87 2.1 westy wont stay running longer than a minute or two. It runs pretty good, then slowly starts to hesitate and eventually die after a minute or two. We can then immediately start it right back up and repeat. very strange, we are stumped.

What we have already tried:
Grounds are clean
Temp sensors and oil pressure sensors( new o2 sensor going in this weekend) entire ignition system is good (timing, coil, distributor, relays, etc.).
fuel pressure is good. All injectors appear to be functioning good.
AFM is good
throttle switch is adjusted good
idle control valve and module are both good ECU is good the purple and white vacuum lines appear to both be leak free

With fuel and spark both good, it must be some kind of electronic issue or air leak, yeah? We are stumped... looking for any ideas.
Kevin