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Injectors Staying Open - gallons of fuel.

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Old Nov 23, 2003 | 01:33 PM
  #1  
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From: Daytona Beach, FL
Car: 88 GTA
Engine: 355 TPI
Transmission: 700 R4
Axle/Gears: 370 BW
Injectors Staying Open - gallons of fuel.

Does anyone know of something that could force all the injectors to stay open? The injectors themselves seem in good shape. Ohms are between 13 to 14 on all eight. I've tested them on the fuel rail and out of the intake and none leaked. It appears that all eight are doing the same thing and everything was fine yesterday morning (until I had installed a new prom with a messed up BIN file) Stock chip has been reinstalled since then.

When I turn the engine over with the spark plugs out, I get lots of gas pouring out of the plug holes. I had 1/2 to a full gallon that had collected in the crankcase. Since then I flushed and refilled with fresh oil.

I felt that the injectors could have been binding and raised the fuel rail to release any possible pressure on them. I crank the car 5 - 10 revolutions get out and fuel pressure is close to zero, gas all over the headers from the plug holes, I disconnect the battery and after a few seconds fuel pressure raises to 15 - 20 and then very, very slowly starts to drop.

Could something be wrong with the ECM or a short in the wiring harness? It seems like the injectors are wide open and spraying constantly while cranking.

HELP!
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Old Nov 23, 2003 | 03:39 PM
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From: Detroit, Michigan
Car: 04 Xtreme Blazer
Engine: 4.3L V6
Transmission: 4L60E
yes, a short to ground on the control wire/s (the one/s to the ECM from the injectors) will hold all the injectors wide open
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Old Nov 23, 2003 | 04:26 PM
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From: Daytona Beach, FL
Car: 88 GTA
Engine: 355 TPI
Transmission: 700 R4
Axle/Gears: 370 BW
Dave, thank you so much for the reply. Right before checking your post, I had found one of the injector wires (purple and black) was grounding into the block (from a pinched wire), could that make both banks stay open or just one bank?

:hail:
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Old Nov 23, 2003 | 04:36 PM
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Car: 04 Xtreme Blazer
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both i think, but not positive, might want to inspect the other side to be sure
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Old Nov 23, 2003 | 04:38 PM
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From: Fairview Heights Illinois
Car: 1986 Irocz
Engine: 305 TPI
Transmission: 700R4
Axle/Gears: 3.25:1
Yes both because they are all wired together. They all fire together at the same time = batch fire.
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Old Nov 23, 2003 | 04:50 PM
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glad to see you found the problem jo
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Old Nov 23, 2003 | 06:15 PM
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From: Daytona Beach, FL
Car: 88 GTA
Engine: 355 TPI
Transmission: 700 R4
Axle/Gears: 370 BW
Thanks guys, I'll double check for other wires tomorrow and provide an update.

BTW, reason I thought they were seperate is that the pink/black and green/black injector wires (one for each bank) have seperate pins on the ECM.
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Old Nov 23, 2003 | 07:33 PM
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From: In reality
Car: An Ol Buick
Engine: Vsick
Transmission: Janis Tranny Yank Converter
Originally posted by jo88gta

BTW, reason I thought they were seperate is that the pink/black and green/black injector wires (one for each bank) have seperate pins on the ECM.
Checking from pin to pin will show 0 resistance. The 730 only has one injector driver switching devise in it.
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Old Nov 23, 2003 | 10:38 PM
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From: Macedonia ,OH
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Common Sympton of the edelbrock base. Put 1 washer under the fuel rail on all 4 cornors and problem solved. When tighting down the fuel rail with no washers the injectors are grounding themselves out. This has happen to numerous people on this board. So a search and You will see.
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Old Nov 24, 2003 | 08:42 AM
  #10  
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From: Daytona Beach, FL
Car: 88 GTA
Engine: 355 TPI
Transmission: 700 R4
Axle/Gears: 370 BW
Originally posted by 305sbc
Yes both because they are all wired together. They all fire together at the same time = batch fire.
Grumpy are you saying the above statement is only true for the 730 ECM? It seems to me that each bank has a seperate driver. Could you please clarify?

Regards!
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Old Nov 24, 2003 | 08:49 AM
  #11  
jo88gta's Avatar
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From: Daytona Beach, FL
Car: 88 GTA
Engine: 355 TPI
Transmission: 700 R4
Axle/Gears: 370 BW
Grumpy, sorry about that. I get what i desirve for posting the same thing in two different areas of the board. You already answered this question under my other post. In a desperate effort to get a quick answer I double posted. For the others who want the full answer here is a link to the other post.


https://www.thirdgen.org/techbb2/sho...59#post1573959

Thanks again! :hail:
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Old Nov 24, 2003 | 02:40 PM
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From: In reality
Car: An Ol Buick
Engine: Vsick
Transmission: Janis Tranny Yank Converter
Originally posted by jo88gta
Grumpy are you saying the above statement is only true for the 730 ECM? It seems to me that each bank has a seperate driver. Could you please clarify?
The 1227730 and 1227165 both only have single injector drivers in them. The 1227749, has two.
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