Kevin,

Same thing happened to me, turned out the wiring that plugs into the
thermostat housing was not in all the way so the ecu thought the
engine was never warmed up.  And if its connected make sure the
contacts are clean.

Tim

>I just had the heads done on my '90 Vanagon, it's back
>together, it's not running well and the mechanic is
>stumped. It runs when cold, as it warms up it runs
>very rough and rich, black exhaust, etc. He has
>checked the engine ground, the wiring, changed the o2
>sensor, checked air control unit, changed the temp
>sensor, even tried a different ECU ...all to no avail.
>I've seen this same problem (after valve/head work)
>posted on a tech site...but couldn't glean a solution
>from the listing. Any suggestions out there?
>Kevin OBrien@yahoo.com
>
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