PCM code TDE1 is the one you want, it's a truck code but I see no reason it won't work in a van.

With a chip it will completely override your pcm so you can basically get whatever code you want, regardless of your PCM.

If your still unsure call Jodi at DPTuner he'll fix you up.

 

The chip needs to be written for the correct hardware though, so we will need to know the code. If it were a 1997 Federal Auto truck, the code TDE1 would work. However, in the E-series, it may be a DPC-202 if it very early 1997, but it is going to be a DPC-315, DPC-405, or DPC-435 if it is later.

Really can't guess with vans, as they switched around a lot. Gotta get that code!