Parked my truck for about a month and now it won't start. I had no gas in the injector tube and thought it was the fuel pump. Jumped out the pump relay and it works and pumps fine, but still won't start. I tested all three relays and they pull in with anything over 5 volt, but it seems I'm only getting around 3 volt at the relay coil. I changed out the computer but still no go. It seems to be an electrical problem getting power to the relay and possibly the injectors. Seems to me as tough the injectors are not putting any fuel into the cyl. I do have spark. Any thoughts?

 

You have spark, are you getting air? Is the air intake clogged ?

have you tried starting fluid in the intake? This happend to me years ago, never on a never model truck, I used some starting fluid in the intake and she started right up.

 

I have done some research on the above problem. Here is some possible causes that I have found.

Looose, corroded or broken battery terminals

Fuel not reaching the injectors check for a clogged fuel filter, or lines also make sure the fuel pump is working properly and make sure that the fuel tank vent lines are not kinked or clogged.

dirty or clogged fuel injectors

low cylinder compression...run a compression test

defective ignition coils or broken wires leading to them

damaged ignition components

broken or bad wires in the starting circuit

valve timming off due to timming belt/chain defective or broken

defective MAF sensor

These are some of the possible causes I have discovered that could be the reason your truck is not starting.

 

have a 1990 F350 having problems with it dying while driving or at a idle..It loses RPM's almost to 0 then either comes back or dies...Truck recently died completely and wasnt getting spark, so I replaced the coil, plugs, wires, ignition module, then distributor, after the distributor it started running again, and actually pretty good..But started driving and at first had a very slight sputter, then got worse....tryed adjusting timing and no help with the problem..Could it be crankshaft position sensor?? Seems like very similar problem when I read up on the crankshaft pos. sensor problems....please help...
just bought this truck for a new job and could't even show to work the first day....

 

I bought a code reader, but get no codes when trying to start the truck. Does this mean the EMC is bad?