Engine 91 5.0 no start ECU pin 57 trace

1957fan

New Member
Feb 19, 2020
2
0
1
57
Washington
So I have an interesting crank with no start. I have done almost every check and have determined that I have no inj pulse and the PIP is good as I had to replace the distributor due to a bad bushing. I have check all wiring to the ECM and they are all good (used a DVOM). I replaced the capacitors in the ECM as two were bad and still no start. the 10 pin connections are good. My fuel pump still runs continuously, engine light is dim and no 5Vref at the TPS, EVP or BP sensors. I had these same reading before I replaced the capacitors. The sensors are getting about 1.5V at best. I am sure this would cause a no start. I have been looking at the circuit board and I believe I have a broken trace on pin 57 (Vpwr) at the 10MF capacitor. (see pictures) Can anyone verify that this capacitor is getting VPWR off of pin 57? I do not have another ECU to verify this. My car is pure stock with no modifications and I have gone thru the complete diagnostics from this forum and everything still goes back to the ECU as the bad item. I can add a wire to the capacitor to pin 57 to bypass the trace. I hope these pictures show the break.
 

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1957fan

New Member
Feb 19, 2020
2
0
1
57
Washington
Well I did some more testing and verifying what I saw on the board. Well the trace from Pin 57 to the capacitor was broken by the corroded Capacitor thus interrupting Vpwr from pin 57. I soldered in a couple of single strand wires from pin 57 to the (+) side of the capacitor and the car starts and runs good. If you look in the picture that I circled you can see the broken trace. Back on the road....
 

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