[Kirsa]

I´m having two codes on my 2006 cadillac dts 2006 with vin #1g6kd57yx6u108037
The codes are p0304 and p0204 I have changed both the coil and injector and suspect the Harness to be the culprit. How do i check the wires from the ECU to the injector if they are shorted to ground and keeping the injector open all the time?
If someone has a diagram it would be very nice?

Thank you in advance.

 

[Superjim]

P0204... Faulty fuel injector 4....Fuel Injector 4 harness is open or shorted....Fuel injector 4 circuit poor electrical connection
P0304.. Misfire on cylinder 4

 

[Kirsa]

Thank you superjim!

I believe its the harness thats causing the car to blow raw fuel through the engine due to open injector. I have tried a new ecm but no change. Getting frustrated with my cadillac.
Thanks for any possible suggestions?

 

[danog]

Just unplug #4 injector. If you still have the same problem, it’s a bad injector. Injectors open by the ECM and close by fuel pressure.

 

[Kirsa]

I believe its a intermittent problem cause the vehicle will drive fine for a while and the all of the sudden throw code p0204 and p0304 and dump raw fuel lots of smoke and service stabilitrack comes on as well as MIL light. The car shakes and runs really rough. The injector stays open and thats why i think there is an open in the injector driver circuits?
@ danog I don´t understand how the fuel pressure closes the injector? I thought its was the ECM´s driver wire that opens and closes the injector.
Can you please explain it for me?

 

[chopperb]

Here is the wiring diagram of the fuel injectors.

 

[danog]

Move injector 4 to 6 and if it moves to 6 you got a bad injector. Have you had the injectors cleaned? The injector has 12 volts on one side and the ECM grounds the injector (ECU controls the duration of the opening and closing of the injectors) If you have an open in either circuit the injector stops working.

Check the dip stick. If its dumping gas the oil level will over full and smell like gasoline and can lead to more problems.

 

[Kirsa]

Thank you very much for the info danog and chopperb. I will try to check and move the injectors. yes the injectors has been cleaned
I let you know if it works

 

[Kirsa]

Problem solved it was the signal wire for the injector that was shorted to ground due to the sharp plate where the whole wire bundle nicked the wire.
thanks guys