So this doesn’t begin until I put it into a forward gear, but after about 30 sec of smooth running, I will get a sudden momentary loss of power, then a surge, which repeats and intensifies as the van lurches forward until the engine finally stalls. Throwing it into N in the middle doesn’t help. Babying the gas had no effect. It happened both at higher(2.5-3K) revs and at lower (.8-1.5k). After killing the battery starting and restarting it just to keep it moving, I had it jumped, at which point I sat with it in P for 20 min to charge the battery and in all that time, it ran fine. I’d love to hear some possible diagnoses. Don’t know if I should have it towed from where it’s sitting, or try to drive it to the shop, or if it’s something I can repair myself (think 1-star difficulty).
Did you resolve the problem?? My ford freestar is having same issue.
It’s such a vague symptom, hard to say. A shop would check for stored diagnostics codes and go from there checking for anything visually wrong in the engine compartment, stuff affecting intake manifold vacuum (in particular the brake booster) , verifying the routine engine maintenance items are all up to date, then checking fuel pressure and ignition system.