454 TBI wont stay running.
I am working on a 1987 Chevy 1-ton that has the 454 with TBI. I can start it and it will run anywhere from 10 seconds to 2mins, it studers then will idle up and down before it just stops. This morning I changed the Fuel filter on the passenger side rail. (NO JOY) I can hear the Fuel pump priming and it sounds fine. I took the Air intake filter dish and cover off and can watch the fuel come out of what I believe to be the injector nozzles, it flows very well and does not sputter and appears to be working fine. At that point I ruled out the fuel system and I have moved on to the ignition system, after verifying the plug wires were correct we pulled the cap and looked at the rotor button it was pretty rough so I replaced that and the cap as it was really rough (corrosion on the studs) while in the distributor I replaced the ignition module as well. I reassembled and re verified the wires to the right place, again no joy. So now I am at a loss. I know that the ECM plays a big part in the ignition and fuel setup however I am not sure which of the 7 or 8 data parts it controls to look at. I am getting 14.75 volts output at the ALT. and 13.75 from the Batt. The plug wires were replaced about 2 years ago and ohm out fine. Any help would be great.