I found out what was causing all the whacked out problems I've been having with my TBI. The fuel pressure was too low because the rubber isolator line in the pickup had a hole in it. I don't have a test gauge so I checked when I first got it together by cracking a line open and seeing that it had quite a bit of pressure and that it held pressure when the key was off for at least 30 minutes or so. This was all part of pressure testing my hand made hard lines. Well, it looked good when I put it together but, apparently the rubber line was weak. When I looked at it today, it was soft, spongy, split all around the ends, and had one nice little hole in it that you could not see unless you flexed it a little bit. While in there, I changed the pump, sock, and the filter. Something else I've never seen before, the filter was broken loose INSIDE! Just flopping around in there not filtering anything. With a new pump and filter, I no longer have the surging, backfiring, OR the EGR problems. Man, wish I had gone on and gotten the under hood pressure gauge that goes in-line rather than waiting and trying to find a cockpit mounted gauge like I want. Sure would have saved some time. So, lessons learned from my wasted time. If your gonna mess with fuel injection, you MUST have a pressure gauge! Russ 85 K30 CUCV, 350 TBI, TH400, 205, D60/C14, 4.56 Locked Some day: 4" lift, 44" tires, massive cutting, shorter wb and rear overhang.