I would like some advise on the following. I have a GMC Vandura 2500 day van. 1992, V8 5.7L. I have lovingly restored and customised my van (Turkish). I seem to have developed a running problem. I think it was there before but I cleaned the EGR valve and now the problem is worse. The problem is that when I put the van in gear and try to drive forward, the engine wants to stop - on tickover it is fine. If I try to rev it slowly, the engine wants to stop but if I rev fast, it seems to be OK. I did notice when I drive that after a run, when I stopped (at a junction) and then went to drive away, the engine stalled. I have checked the EGR valve by pushing the diaphram by hand on tickover and it cuts the revs down/stops the engine (as per the manual). I have also tried another ECM and the problem is still there. I have tried another thermal vacuum switch but problem still there. Everytime I rev the engine and release the throttle, the engine wants to cut out (fuel starvation?). If I take the small vacuum pipe off of the egr valve, then there is not a problem. Any suggestions would be very much appreciated. I look forward to hearing from you all. Keith

 

did you ever figure this out? i have a buddy that has the same issue. let me know.