I'm not quite sure what's wrong with my fuel injectors. I removed them as one unit with the fuel rail to check for leakage on one injector and as soon as I turn the key to the on position all four of them shoot fuel. I'm not cranking the ignition, just turning it to the on position. I heard that if you remove fuse 7.5A under the hood you disable the ECU and from there if you turn the key to the on position and it doesn't shoot anything means your ECU if bad. I'm not sure if this is valid from but I tried it as well. My injectors continued to shoot fuel. Any idea what the potential problem could be?

 

My guess is the ground triggers are shorted out to ground, [possibly inside ECU/ECM].

Unplug all the injectors a test the trigger leads, [lead that is a different color at each injector].

Because this only happens once the ign. I turned on, it is a good bet the ECU/ECM is the problem.

The 7.5A fuse is only memory for the ECU/ECM, removing it has no effect on the ECUs operation. 94

 

What kind of car is this on. This can happen on DC2 chassis due to water on a plug under the backseat.

 

What does the "plug under the back seat" have to do with the fuel injector "trigger" leads??? 94

 

It will back feed voltage and cause these problems. I am not the only one to have this happen to me. I spent a full day on a customers car trying to figure out how the fuel injectors were dumping fuel. It actually hydro locked the engine.

 

My car is an EJ8.


Anyways I tested the leads and I'm having constant voltage. This verifies the ECU short but how do I know it's the ECU and not the wiring?

 

Thanks for the replies, I swapped the ecu out and it stopped shooting fuel at on.

 

Back-feed voltage, to where and what?.

Even a short at the fuel pump harness plug would only effect the PGM-FI Main Relay at most and/or blow a fuse.

Phoodles glad you got it fixed, just one thing, the injectors are supposed to have constant power, [with ign. on] the ECU/ECM supplies the ground pulse, yours was supplying a constant ground. 94

 

Ok then by your conclusion I must be making this up, or don't know what I'm talking about. In theory, I agree this should not have been causing the issue. I also had erratic fuel pump and main relay operation. So as I took the backseat off to access the pump area I notice the wet and corroded connector. Once I repaired this connection the problem was fixed and the injectors no longer sprayed fuel with ignition power.

We all have something to learn from each other, please keep your mind open. The world has enough know it alls.

 

My job, Dave Ward Auto Electric, I do this all day long, I still fail to see how anything happening to the fuel pump connector would effect the ECU/ECM.

As for keeping an open mind, it is why I ask, I have gone over the wiring diagrams and can see no way it could happen, the only "connection" between the ECU/ECM and fuel pump is the control lead from the ECU/ECM to the fuel pump relays coil and that is a ground and it is not a direct connection.

Maybe if you could explain how it happened, [or could happen] then maybe all of use could learn something. 94

 

That's the thing, I can't explain why it happened. I agree with your assessment, however I repaired the connection and it fixed the issue. It spent 2 weeks at another shop prior. I had to soak up the fuel in the cylinders and the oil had an extra 2 quarts that was pure gas. I have since seen this issue come up in threads in here as well with the same scenario. That's why I posted, to try and help someone out, not because I was bored or like to type random BS. The OP has since found his issue so it no longer matters anyway.