Well i got a 94 bronk as my mud truck. Ran awesome for a few months, mostly jumping the **** outta it. Well I was doing a huge jump and then I landed and it stalled out. No fuel pump. So I checked for power at the intertia switch none, ran a power wire too the swith to see if it would work. Yess it runs, but still doesnt start. Started to ck fuses and relays. Good, checked for power and ground to the ECC relay and Fuel pump relay. I have power but was losing it goin to the ecu, found corroded wire at ecu, got power at ecu now, still no start, fuel pump still not running, LB/O is the ecu ground sig, for the fuel pump relay, wire good to the ecu, if I add ground then the pump runs, still no start, have to ck for injector pulse and spark, but thats hard alone. Anyone think bad PCM also?

 

How about the PCM relay next to the Fuel pump relay. It has to actuate so the Fuel pump relay can.

 

Yea that is sending power to the fuel pump relay, but the PCM is commanding ground to the relay too power it up.

 

Try shorting pin #2 to to pin #6 of the EEC Self-test plug and turn on the key and see if the pumps run. I know you said you grounded pin #6 and they ran but do the above test and see if they run that way.
If they do not run that way then you have a bad Computer ground over near the battery.

 

Ill try that, I checked them grounds over there seem fine, do you have a pin out of the ECC plug or its numbered? Ill go look now and see.

 

Pin 2 is a power source, and pin 6 is what needs the ground. But I still jumped it and no go.

 

Pin #2 SIG GND is ground through the computer pin #46. Pin #6 is coming from the coil of the fuel pump relay. The other side of the fuel pump coil comes from the EEC power relay.

Computer pins 40 & 60 go to the body ground or the NEG Post of the battery.



Pin #2 ground through the Computer (SIG GND J1-46):


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There was a #2 by a defferent pin, let me go retry it, I printed out some stuff from work, and im gettin ground on 40 and 60

 

Just went out and rechecked, pin 2 has power too it. Pin 40 and 60 both have ground.

 

Pin #2 I am talking about is on the test connector, not the computer.
It is pin #46 on the computer plug.

Pin#2 on the computer plug is the brake light switch (BOO switch).

 

Yea pin 2 on the ECC Test plug has power to it.

 

Then you have lost the ground to the computer or you have a bad computer plug or computer.
There should be a wire going from the NEG post of the battery to the RH front of engine compartment, front of fender apron. Photo below.
There should be a wire (black with a white stripe) leaving this ground point and going to pins 40 and 60 of the computer plug. This wire also has a splice before it gets to the computer and goes to the MAF sensor.



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I have the 2 little ones, but the big isnt there, but the bronk used to run even when it was like that before. Ill add the strap from the neg to that post, I do think that the computer is fried tho.

 

Just made a ground from that post to the battery, still hot on pin 2, any other tests to see if ecu is bad?

 

Unplug the computer and jump pin #60 or #40 to pin #46 on the computer plug and see if pin #2 is still hot with your test light. Do not use a meter to test pin #2 as a meter may lie to you at this point.
If it is still hot you have an ope wire someplace and the computer is OK at this point.





Note after the "/" in the wire color is the stripe on the wire color.
GY/R would be a Gray wire with a Red stripe.
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