Everything, and I mean everything, has been checked, rechecked and rebuilt, carb, fuel pump, distributor, timing, compression, all vacuum lines, EGR, PCV, float, all fuel lines and tanks, tank switching valve, spark plugs, wires, etc., etc., etc.

Early on I thought it was the EICM (electric ignition control module) but I had that triple checked by my local parts house and it checked out good.

Lately I decided it was fuel starvation which lead to the rebuilding and checking of all of those compenents.

The truck ('76 F250 4X4 360 C6) can run for miles absolutely flawlessly through several fill-ups but eventually it will start sputtering, backfiring and coughing to a complete stall. It will always start up immediately and run for a few seconds, a few minutes or a few hours. Sometimes it will happen at start-up when cold and sometimes only after running for awhile.

As stated earlier I thought it was fuel starvation until it quit one day and I removed the air cleaner and carb top expecting to find an empty float bowl but to my surprise the fuel in the float bowl was at a normal operating level (about 3/4" to 1" below the top of the bowl and the float was floating freely). That leads me to believe that the problem is electronic.

I'm also posting this in the carb forum under "fuel starvation driving me crazy" and a guy responded that his '77 did the same thing, and his EICM also checked out "good" at the parts house, but replacing the EICM solved his problem.

HELP!

 

I responded in the other thread. Do you want to dump this thread or move the new responses from the other thread down here and let the other thread die out? It's too confusing to have both.

 

My $.02, If I was experiencing this on my '73 390 4V

Sputtering= vacuum leak in hose or intake manifold, faulty choke, sticking or incorrect power valve, particals in the jets, water in fuel

coughing= arcing in the distributor, pre-ignition, excessively high or low resistance in coil or plug wires

backfiring= unburned fuel, faulty or incorrect power valve

dieing=fuel starvation, in tank filters, tank switching valve, vapor lock, fuel bowl boiling, cracked fuel line that allows air to pass instead of fuel

 

I am now quite certain that all of my problems were caused by a slowly (over a year of daily use) failing ECU. The truck got so bad that if finally would hardly run at all. I installed an ECU I pulled off a truck at a boneyard and for several days now the truck runs flawlessly. It's running better than it has for about a year. I'm keeping my fingers crossed and if I get a few more days of perfect running I'm going to reinstall the old ECU in the middle of a trip just to see if the old problems occur. I had the old ECU tripple checked at my local parts house by a guy who seemed to know his stuff and it checked out good all three times so I'm finding it hard to believe that this is actually the problem. On the other hand I certainly do hope the boneyard ECU solves the problem.