1994 manual 5 speed codes interpretation, paperclip test engine off

[fabianoliver]

Ok, i've just finished the paper clip test with off engine looking at the Check engine light.

My truck is a 1994 5 speed manual, it doesn't came with O2 sensors installed from factory, just a ford plug, a straight jumper.
When i turn on the key, some seconds in "black", then it flashes fast and it shows some codes in two groups:

556
556
-----------
542
556
542
556

That's it.

I've some codes and results at:

Aerostar Van/Wagon – Bronco – Econoline/Club Wagon – Explorer – F-Series – Ranger (1992 – 1997) – TroubleCodes.net

www.troublecodes.net

but i would like to be helped, cause i'm not sure what they mean.
Any help on that will be very helpfull.

The X runs ok, but it consumes hard in the city: 11.7 when i take care, in the highway it's 20,5-21 at 62 miles

i don't know if there's a test with the car on, looking at the check engine light, it is done too?

txs!!

 

[dvdswan]

From the chart it looks like 556 and 542 are things with the fuel pump. Have you tried a fuel pressure test?

 

[fabianoliver]

From the chart it looks like 556 and 542 are things with the fuel pump. Have you tried a fuel pressure test?

Hi!, no i didn't.
But wht i've learned 2 mins ago, is that the pump should activate and then stops 2 seconds later when key is moved just prior to crank.
My fuel pump is allways on when i turn the key, even a little.
May be is related to that?