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I will be searching the forums here shortly, but I am semi-stranded on a 1,750 mile road trip with 5 kids under 10, over 500 miles from both my origin and destination. I have a 2001 Suburban I bought with 260,000 miles on it. I'm now pushing 270,000 I made it to a hotel nearby a Chevrolet Dealer, but they don't open for service until Monday. I was cruising at freeway speeds and suddenly the truck engine died and began coasting to a stop. I put the truck in neutral, restarted it, and it fired up and popped back into drive. About 150-200 miles it started happening more frequently. When the engine loses power, the tachometer shows the engine speed dying out, so it is not a total loss of signal from whatever provides the signal to the tachometer. After dying out, the engine will fire back up and idle with minimal extra cranking. The engine starts up and idles well at these times, and I have had to idle it with the family in it and it runs the AC no problem at idle. I have not had the condition pop up at idle. Sometimes, the engine will recover itself and resume accellerating as we are coasting if I feather the pedal. I have an AutoEnginuity scanner and a decent array of tools that I travel with. MIL is not on. I have some history codes for: P0461: Fuel Level Sensor Circuit Range/Performance (I believe this code was never cleared from before I replaced the sending unit previously) P1172: Fuel Transfer pump Flow Insufficient - This one kind of makes me wonder. On the trip, due to having the kids in the car, I have refueled at various levels with the engine running for A/C. Alldata says this code will not set if P0461 is present. P1431: Fuel Level Sensor 2 Circuit performance. The only way I could see the secondary fuel pump effecting drivability, aside form usable fuel, is if the secondary pump failure has caused it to become an excessive current draw. When I bought the truck, the fuel gage was not working, which I traced back to the primary sending unit in the tank. At around 265K miles. I replaced the fuel pump and sending unit assembly at this time with a new AC Delco OEM replacement part. Since that replacement, I have made the same 3,500 round trip road trip without issue about 1 month ago. One difference this time is that the ambient temperature this time is considerably warmer outside, however the coolant and trans temp gages have been riding right at where they normally do. Prior to that last trip as well, I put AC Delco Irridium spark plugs gapped at .045", and a 180F thermostat in the truck. The only other issue that I had was that at one point the EGR became stuck open by a small piece of stray carbon that would cause the truck to not idle. When the stalling symptoms first surfaced on this trip, I put a new AC Delco fuel filter in the truck and replaced the primary fuel pump relay just to rule them out, I would find it odd that a fuel pump would fail at that juncture at 5K miles old, however I am planning to get down to AutoZone and purchase a fuel pressure gage just to check that out during the moments when the problems are being experienced. The old fuel filter didn't seem restricted with a blow-through test. I do know this truck has both a camshaft and crankshaft position sensor, and I have seen a lot of similar symptoms that relate to the failure of one or both of these. I think that's where I'm looking next if the fuel pressure checks out. Am I correct in assuming that the engine would throw a DTC if an ignition coil or coil group was intermittently failing? Any help greatly appreciated! Thanks! Steve 2001 Suburban 2500 8.1L 4x4, 270K Miles