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Cant get injectors to fire.

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Old Dec 8, 2013 | 04:22 PM
  #1  
Eli346's Avatar
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Car: 1989 Camaro
Engine: 305 Tbi
Transmission: 700R4
Cant get injectors to fire.

What makes the injectors fire? I have power on both sides on both injectors and if i ground out the one side it will spray fuel so i think they are good. When i turn the engine over there don't click or spray fuel so what do i check next?
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Old Dec 9, 2013 | 12:43 PM
  #2  
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Re: Cant get injectors to fire.

Originally Posted by Eli346
What makes the injectors fire? I have power on both sides on both injectors and if i ground out the one side it will spray fuel so i think they are good. When i turn the engine over there don't click or spray fuel so what do i check next?
Seems your ECM is not supplying ground. No ground, no current flow, no current flow no solenoid movement.

If you have no spark, either, I'd suspect the distributor.

Could also be a wiring harness problem, or a failed ECM.
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Old Dec 9, 2013 | 06:02 PM
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Car: 1989 Camaro
Engine: 305 Tbi
Transmission: 700R4
Re: Cant get injectors to fire.

Originally Posted by Schurkey
Seems your ECM is not supplying ground. No ground, no current flow, no current flow no solenoid movement.

If you have no spark, either, I'd suspect the distributor.

Could also be a wiring harness problem, or a failed ECM.
I have spark and the car will run on starting fluid. When i got the car the computer wasn't hooked up and there were two cut grounds that i just grounded to the same spot on the body so im not sure if that could be effecting it or not.
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Old Dec 10, 2013 | 10:47 AM
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Re: Cant get injectors to fire.

Do you have a functioning ALDL and CE light? I believe ECU need a dist ref pulse and maybe oil pressure(not sure on this one). ALDL functionality will help.
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Old Dec 11, 2013 | 10:12 AM
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From: OC CA
Car: 75 Beast
Engine: 383 +EBL Flash
Transmission: 700R4
Axle/Gears: 4.11 with 33"
Re: Cant get injectors to fire.

Originally Posted by Ronny
Do you have a functioning ALDL and CE light? I believe ECU need a dist ref pulse and maybe oil pressure(not sure on this one). ALDL functionality will help.

DRP pulse signal = YES
Oil pressure = NO
Grounds = YES
Ignition +12V = YES
Check VATS function if equipped
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Old Dec 16, 2013 | 10:54 AM
  #6  
Eli346's Avatar
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Car: 1989 Camaro
Engine: 305 Tbi
Transmission: 700R4
Re: Cant get injectors to fire.

Originally Posted by RFmaster
DRP pulse signal = YES
Oil pressure = NO
Grounds = YES
Ignition +12V = YES
Check VATS function if equipped
It did have a vats issue before but i put in a resistor and bypassed the starter relay at the same time so what im wondering is if there is a vats problem and the starter relay is bypassed will the engine turn over? Because if it will it could be possible there's still a vats problem and i just have it bypassed for the starter.
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Old Dec 16, 2013 | 12:23 PM
  #7  
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From: OC CA
Car: 75 Beast
Engine: 383 +EBL Flash
Transmission: 700R4
Axle/Gears: 4.11 with 33"
Re: Cant get injectors to fire.

Originally Posted by Eli346
It did have a vats issue before but i put in a resistor and bypassed the starter relay at the same time so what im wondering is if there is a vats problem and the starter relay is bypassed will the engine turn over? Because if it will it could be possible there's still a vats problem and i just have it bypassed for the starter.

Read and review (your answer is in this tech article) :

https://www.thirdgen.org/vats_passkey_system

//RF
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Old Dec 16, 2013 | 02:38 PM
  #8  
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Car: 1989 Camaro
Engine: 305 Tbi
Transmission: 700R4
Re: Cant get injectors to fire.

Originally Posted by RFmaster
Read and review (your answer is in this tech article) :

https://www.thirdgen.org/vats_passkey_system

//RF
"This method was selected to prevent the simple powering or grounding of an ECM input to enable the fuel injectors. The signal is only needed during cranking to enable the injectors." Is this saying that if its vats there will be no power to the injectors even when not cranking? Not sure if I'm reading that right.
And none of the security lights or any of those lights come on such makes me think they don't work at all
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Old Dec 16, 2013 | 03:53 PM
  #9  
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From: Saratoga Area, New York
Car: 1990 Formula Firebird
Engine: 305 TBI (LO3)
Transmission: WC T-5 out of an 88 T/A
Axle/Gears: 10 bolt, 3.42 & Torsen Posi
Re: Cant get injectors to fire.

If the 'SECURITY' light does not illuminate for a few seconds when you first turn the key on, that is a problem. The 'SECURITY' light should come on for a second and then go back off. I had a similar issue with mine a few years ago, with the light not turning on at all. The VATS module is probably bad, as was the problem with mine.
Basically, you have three options.

1) Now if you're concerned about your car getting stolen you can still get all the parts to replace the VATS system, the module and a new ignition cylinder should fix your problem for a hefty fee (I think when I priced it it was going to be $250+)

2) You can tune out VATS in the ECU if you know someone with software and a chip burner.

3) You can buy a bypass kit that will provide the ECU with the signal it expects to receive from the VATS module. I have seen a bypass kit recommended on this site made by Baker Electronix. You should be able to find it by googling (Baker Electronix VATS Bypass).

I think the cleanest way would be to tune out VATS, it would save you from hacking up any of the factory wiring, but I understand that's not always an option.

Good luck
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Old Dec 16, 2013 | 04:15 PM
  #10  
Eli346's Avatar
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Car: 1989 Camaro
Engine: 305 Tbi
Transmission: 700R4
Re: Cant get injectors to fire.

For some reason the baker site won't open on my phone but this should do the same thing I'm assuming
http://www.ebay.com/itm/GM-VATS-or-PASSkey-II-Bypass-Module-For-LS1-and-LT1-/281179660936?pt=Motors_Car_Truck_Parts_Accessories&hash=item41779d2288&vxp=mtrI think ill order it and find out
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Old Dec 16, 2013 | 08:20 PM
  #11  
Formula 305's Avatar
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From: Saratoga Area, New York
Car: 1990 Formula Firebird
Engine: 305 TBI (LO3)
Transmission: WC T-5 out of an 88 T/A
Axle/Gears: 10 bolt, 3.42 & Torsen Posi
Re: Cant get injectors to fire.

Yeah, looks the same as the Baker one, except that the baker one was in a nice little box.
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Old Jan 1, 2014 | 04:44 PM
  #12  
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Car: 1989 Camaro
Engine: 305 Tbi
Transmission: 700R4
Re: Cant get injectors to fire.

So i wired in the module to the blue wire on the ecm and im still not getting any injector fire. The module is sending the 30hz signal right now does it need the 50hz instead?
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