I have an '88 Westy and if has developed the following quirk.

When cold, and starting off from a stop, in 1st and 2nd gear from 0 to
about 3,500 rpm, it acts like someone has thrown an anchor out the back.

It is as if an invisible hand is holding onto the van. Once I shift to
3rd, or break past 3,500 rpm everything is fine.

Does this sound like a temp sensor or O2 sensor problem?

Todd Last