Injector Driver
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From: Moorestown, NJ
Car: 88 Camaro SC
Engine: SFI'd 350
Transmission: TKO 500
Axle/Gears: 9-bolt w/ 3.23's
I have one of those as my test bench ecm. Flashes the lights like its working properly but fails to be able to drive actual injectors at times. I wonder what causes the driver transisters to go bad in the first place?
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Originally posted by dimented24x7
I have one of those as my test bench ecm. Flashes the lights like its working properly but fails to be able to drive actual injectors at times. I wonder what causes the driver transisters to go bad in the first place?
I have one of those as my test bench ecm. Flashes the lights like its working properly but fails to be able to drive actual injectors at times. I wonder what causes the driver transisters to go bad in the first place?
The lower duty cycles don't seem to hurt them. But load, will. First they get a lil erratic, and then fail open. In my experiences.
Some saturated injectors internally short out (at varing levels), and can overload/heat the drivers. If they *short* totally and quickly the ecm isn't run long enough to ruin the injectors. It's the slow failing injectors that kill them.
The 2.8 and 3.1s with the 730 usually get a full no start when the injector resistances drop to low. So replacing the injectors is the healing solution (we typically).
A good way to see it and kill a 749 is running 8 P+H injectors instead of 6. Low DCs not problem, 4K RPM for a few minutes, and you can feel the ecm get hot, and eventually they'll start sounding erratic, and then quit. I've had that same routine happen 3x when testing 749s.
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iTrader: (2)
Joined: Jan 2002
Posts: 9,962
Likes: 5
From: Moorestown, NJ
Car: 88 Camaro SC
Engine: SFI'd 350
Transmission: TKO 500
Axle/Gears: 9-bolt w/ 3.23's
Originally posted by Grumpy
Heat.
The lower duty cycles don't seem to hurt them. But load, will. First they get a lil erratic, and then fail open. In my experiences.
Some saturated injectors internally short out (at varing levels), and can overload/heat the drivers. If they *short* totally and quickly the ecm isn't run long enough to ruin the injectors. It's the slow failing injectors that kill them.
The 2.8 and 3.1s with the 730 usually get a full no start when the injector resistances drop to low. So replacing the injectors is the healing solution (we typically).
A good way to see it and kill a 749 is running 8 P+H injectors instead of 6. Low DCs not problem, 4K RPM for a few minutes, and you can feel the ecm get hot, and eventually they'll start sounding erratic, and then quit. I've had that same routine happen 3x when testing 749s.
Heat.
The lower duty cycles don't seem to hurt them. But load, will. First they get a lil erratic, and then fail open. In my experiences.
Some saturated injectors internally short out (at varing levels), and can overload/heat the drivers. If they *short* totally and quickly the ecm isn't run long enough to ruin the injectors. It's the slow failing injectors that kill them.
The 2.8 and 3.1s with the 730 usually get a full no start when the injector resistances drop to low. So replacing the injectors is the healing solution (we typically).
A good way to see it and kill a 749 is running 8 P+H injectors instead of 6. Low DCs not problem, 4K RPM for a few minutes, and you can feel the ecm get hot, and eventually they'll start sounding erratic, and then quit. I've had that same routine happen 3x when testing 749s.
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