Digi 2 injector fail anyone had this problem ?

[hantonyc]

Anyone ever had this problem ? 2 of the 4 injectors even if they arent even connected as soon as the fuel pump turn on the cylinders literally fill with gas and very very fast like if 2 of my 4 injectors were shot and were not but not at all holding the gas anymore ?

[Fat Rabbit]

Your symptom could mean that the ECU is shot. The injectors pulse by grounding through the ECU. Before replacing the ECU make sure that the two or three ground wires that attach to the cylinder head usually at a coolant hose flange stud/bolt are intact and in good shape. Sometimes the wires corrode and fall off or lose contact. A common issue is people forgetting to re-attach those wires after working on the head or engine.

Since you are reporting two of the four injectors as "bad," check the resistance of each injector and the continuity of the wiring. To test to see if the ECU is pulsing use an LED test light to check the pulsing of the feed from the ECU. Disconnect the injector harness at the injector buss connection, apply the LED test light leads across the contacts of the wire and have someone try to start the car. The test light should flicker. If you get no results reverse the test light leads and try again. FR

[hantonyc]

already did the pulse test and test light is flicking like it should do, the reason i know its not my ecu its that its doing this problem WITHOUT the injectors connected , is it common to have injectors stuck open ? all my gounds are ok i re-did my wiring about 1000km ago an ran without any problems since yesterday ..

[WaterWheels]

I would say switch the injectors and see if the same two still dump fuel. If they do then the injectors are bad I guess.

[hantonyc]

just replaced the 4 injectors , it still flood the engine immediatly as soon as i try to start it, i guess even if my ecm is shot

[ziddey]

So without the injectors electrically connected, they still open and dump when the rail is under pressure?! Are these injectors known good?

How much pressure at the rail?

[WaterWheels]

Yeah I'm getting confused or maybe starting to question the entire post based on the following two quotes. I was going to suggest in my first response above to check the wiring, particularly the wires under the black cover at the injectors, but it was first said that the electrical connection to the injectors was not connected. So it now seems that the wiring was connected and that the ECU might have been fried as so many do with bad or un-connecetd grounds when trying to start the engine. I think things need to be made clear.

. . . the reason i know its not my ecu its that its doing this problem WITHOUT the injectors connected . . . . it still flood the engine immediatly as soon as i try to start it

[Fat Rabbit]

It is good that your ECU is pulsing the injectors. Since that test is done at the injector buss connection it indicates that the wiring to the buss and from the buss is OK. That leaves the injector buss itself. In operation, the injectors are constantly supplied with 12V DC. They operate when they are grounded by the ECU as I previously mentioned. If there is a fault to ground in the injector wiring harness the 12V DC supplied to the injectors will go to ground before the ECU (path of least resistance) and the injectors will be open as long as power is supplied. That is why I indicated in my initial post that you should check the injector buss wiring as well as checking the ECU pulsing. (Which you indicated in a later post seems to be fine.) FR

[WAGENHAUS]

If the injectors are not plugged in and the cylinders still fill up with fuel. Pull the fuel rail. Do the injectors leak fuel with the key on ????? NO ---- then the injectors are good and the ECM is GOOD. Pull the vacuum hose from the fuel pressure regulator to the intake manifold, and turn the ignition on . Is there fuel coming out of the vacuum line? There should NOT BE. A very common problem and commonly miss diagnosed. If the engine runs the intake manifold should be hot or warm NOT COLD - if its cold there is fuel in the intake manifold. A sign of a bad fuel pressure regulator.

Jim
Wagenhaus