Engine 1 fuse keeps blowing? - 2004 Chevrolet Express

bogus post, fuse told ,is not correct name and now told not it is not blowing,(ouch)
5.3L V8 , now told, ( this fact puts you into the right chapter of the service manual for sure electrics..)
bogus post#2, fuse PCM-B are not blowing but why are you talking about it at all.?? sure other posts else where? guessing?

stop listening to other guessing what is wrong,
all we know is 12vdc power surge, of some kind,
if you looked at the drawings the things that can fail here are huge(vast). I invite you to read the service manual.
yes fuel pumps do short, want to see a pro Duane on youtube , and his scope showing bad commutator segments of a fuel pump?
huge current spikes, sure but that is a guess. (the video is how to find things going bad before they hard fail dead)

so not told , is engine still dead, ? cranks but does not start, , and did you know dead is the most easy failure of all
to find, safe and sound, not moving and dead is easy to test. (like no spark or fuel pressure dead,etc)
hard jobs are failing moving
or is intermittent.
or only in 3 gear
or only up hill.
or only in left turns. (add endless list here) but the point is made.

dead is bliss in my book , and simple tests find out why.
no voltmeter
no scan tool?(real)
no tools at all?
redux #1 (new truths)

Sorry if didn't help brb I a check something that can probs help

what does it drive - search for some shortcut/ burnt device, wear on cable insulation through 20 amps do not blow without reason. Maybe badly connected engine mass connection - check battery connections to start with

that is a dead short, the fuse saved you the ensuing fire.
there are 2 fuses or more... with that name..
old cars love to short things, no lie.
the fsm is the best thing to have, and alldata.com , 2nd.
the older that car the more true that is... and your car is 10x that.
a 1991
is the fuse in the cab BOX? NOT ENGINE BAY?
THE CAB FUSE , HAS these (USA cars, other are DIFFERENT)
no country stated (sigh)
ignition sw AM1
ignition sw AM2
ignitor 1
ignition coil (1 for 4cy, and 1 for v6 engine, unsaid)
on one car there is a IGN fuse 7.5 amps
and runs the ECU and main relay.
there are 3 engines, and drawing for all 3.

get the fsm and use that or login to alldata.com and hope
it covers your engine. (unstated)
22r,3vz,3F

For the ECM 1 fuse to open you obviously have a short to ground , start with the injector disconnected and see if ECM 1 fuse still blows.If it does disconnect crank sensor, also inspect wires for the injectors or any rub through wires here is a diagram

ENG 1 - 20 amp fuse - under hood fuse Box . This fuse powers the O2 sensors heater circuits , Emission - purge an vent solenoids , mass air flow sensor , camshaft position sensor an A.I.R. intake recirculation relay - if your vehicle has it , L31 only
I would look for wires for o2 sensor melted on a exhaust pipe or manifold . Isn't your check engine light on ?

Did you find the prolbem? Im having the exact same problem you have. Mine is doing it after it died and I replaced the starter but now it wont start and the fuse eng cont 1 keeps getting burned out instantly

The ECM1 fuse blowing usually indicates that the fuel pump wires shorted inside the tank. If you drop the tank and remove the module, you will probably find the insulation burned off the gray pump wire.

sounds as if you have a power shortage in the van. first establish what fuse keeps blowing this will help in narrowing down the short.once short is located check all connections ,wires,and plugs.

Before replacing fuses try disconnecting neg battery lead first. If still blows look loose wire under motor