Chevy and GMC Duramax Diesel Forum banner

1 - 6 of 6 Posts

·
Registered
Joined
·
71 Posts
Discussion Starter #1
Rough idle, code P1232, occasionally it will throw 0304. Checked balance rates, inj #4 shows 15 even, the others are all good to go. Checked the cabling at the alt bracket as I found online, all good there. Tested ohms across the connector on the drivers side for #2 & #4, both show .5ohms there so I think the injector or at least the solenoid is good. I'm guessing I have a grounding issue somewhere in the harness? This happened after the dealer replaced the FICM btw.
 

·
Premium Member
Joined
·
179 Posts
Its going to sound stupid but put some dielectric grease on the connections, it cures a lot of little gremlin issues. I think its a loose plug or ground somewhere along your line of thinking. These days we need a bell for our trucks just like motorcycles!
 

·
Registered
Joined
·
1,040 Posts
This is exactly my symptoms when one of my injectors took a crap. Try the electrical connections to that injector first, if not then the injector is toast. 05 or newer truck right?


Sent from my iPhone using Tapatalk
 

·
Registered
Joined
·
71 Posts
Discussion Starter #4 (Edited)
Ok, finally got time to really tear into it. Checked wire harness from injector back to c1 connector at the FICM. Check voltage while running, #2 and #4 both show 24v to ground so looks like the FICM is telling that injector to fire. Balance rate for that injector is 15. Any way to test injector without pulling it? I checked ohms across the injector, it matches the rest, .5ohms. bad injector??
 

·
Registered
Joined
·
71 Posts
Discussion Starter #5 (Edited)
OK, checked the control wires from the CM to the FICM. Key on, ENG off, #4 should be lt blue/black stripe. It has 5v as well as the other 7, so I'm getting control from the ECM, fired engine and checked, still had 5v on #4 but the other 7 bounced at 4.975ishv.
 
1 - 6 of 6 Posts
Top