Stumped (p0203)

[Budneeds2beers]

Hey guys so my dad‘s truck started running really rough. I put my code reader on there and got a P0146 (I think) followed by a P0203 . I ice pick #3 injector clip to no change. So I replaced the connector. I ohm the pigtail from the Bail connector to the injector and I got .5 of an ohm( across all injectors). I wiggled the loom and didn’t have any change in resistance. I don’t think it’s the FICM because it’s not multiple injectors just the one. I even Ohm’d The FICM and I got .711 on number three and .706 on the adjacent. Not sure what to check next any recommendations would help. And to top it all off i went to start my dmax to do a parts run and that sucker is dead as a door nail! Damn my luck!!!!:woott:

 

[Budneeds2beers]

And I just went to crack a beer and sit on the couch and the tv made a pop sound and it just went out!!!:spit:

 

[TheBac]

You failed to mention the particulars of your dad's truck. LB7? LLY?

 

[Budneeds2beers]

Sorry lly all stock. 05,4by, lt, dont know when the injectors were last done. Not to long ago though.

Can you swap 3 and 5 pigtails to see if the problem fallows?

 

[Chevy1925]

when it throws the code, does it sound like its running on 4 cyl or does it sound like its just missing on 1 cyl?

 

[Budneeds2beers]

Knocking like a tracktor. I would say one. Sounds like when you need to pick it but ive changed the connection and ohmed it. Still at .4/5 ohm and I tested for a dead short from the bail connector to the bat. negative and no continuity. Checked the ficm pins all strait no melting and clean. I read something about a bundle under the intercooler pipe? How else can i test ficm? The truck starts and runs fine for a second or two then it tractors. Should I try and disconnect the batteries and see if it will reset anything?

 

[Chevy1925]

when a connector drops out on these, you should loose a whole bank of injectors, not just the one. i have a feeling you are loosing more than just one but the cause is from cyl 3. try swapping the injector with 5 even with one from the other bank and see if the code follows. injector may have shorted internally. make sure the prongs inside the connector on the injector are not bent or broken either. i doubt its wiring related. quick ohm of the injector and others next to it may tell you too

 

[Budneeds2beers]

Ill grab a smaller mirror and take a look at the injecor pins. Like I mentioned ive ohmed all injectors and .5 across. Unless when it’s commanded to fire and then it shorts. Ill swap 5 and three connectors and see what comes of it. Ive seperated that pigtail from the loom and triple checked it for breaks/rub and nothing. Ohmed each wire individually and .1-2 even wigled the wired to see if i could loose connection and nothing.

 

[2004LB7]

And I just went to crack a beer and sit on the couch and the tv made a pop sound and it just went out!!!:spit:

Probably a bad capacitor on the power supply board. Easy repair

 

[Budneeds2beers]

Yeah but its just something else that I’ve got to do..... atleast the dog is healthy!

 

[Budneeds2beers]

Swapped pigtail 3 and 5. Cleared the old codes and started the truck, no dtc’s. Slight lope but nothing crazy.... WTH man. But no codes nothing.... let me swap pigtails back and see.

 

[Budneeds2beers]

Swapped them back started it and nothing. Test drove it a few miles and nothing..... bit i did pick #5 while i was at it. Not sure what the fix is/was.

 

[TheBac]

Thanks for saying which truck it was. Moved to LLY as a result. Good luck.