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Bad ground?

  • Thread starter Thread starter garycroix
  • Start date Start date Jan 5, 2007
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garycroix

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Sep 16, 2005
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GA, wish it was NC
Jan 5, 2007
#1
  • Jan 5, 2007
  • #1
Hello all. 5.0 EFI into 66. I believe I have steady spark. Plenty of fuel pressure at fuel rail. Crank crank crank, no start. I got a backfire when I sprayed starting fluid into intake and cranked it. I suspect the injectors aren't getting signal to fire. I know they have power when key is turned to 'on,' but perhaps they aren't getting the signal to ground out and spray.

Suggestions? Thanks in advance.

Gary in GA
 
F

ForceFed70

That's why they call it "dope"
Founding Member
Dec 6, 1999
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69
BC Canada
Jan 5, 2007
#2
  • Jan 5, 2007
  • #2
garycroix said:
Hello all. 5.0 EFI into 66. I believe I have steady spark. Plenty of fuel pressure at fuel rail. Crank crank crank, no start. I got a backfire when I sprayed starting fluid into intake and cranked it. I suspect the injectors aren't getting signal to fire. I know they have power when key is turned to 'on,' but perhaps they aren't getting the signal to ground out and spray.

Suggestions? Thanks in advance.

Gary in GA
Click to expand...

You may be on the right track. Crank the engine for a good 30 seconds or so, then pull a plug. It should be wet with fuel.

The ground signal that is used to fire the injectors comes directly from the ECU. Could be that the ECU is bad, there is a bad wire, or the ECU isn't even trying to fire the injectors due to a seperate problem.
 
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