Fuel in oil

joshd472

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Oct 10, 2016
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I had the same thing happen to me but I was t making oil. With as much oil as you are making a compression test is the first thing I would do.
 

012duramax4x4

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May 21, 2017
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P0300. P0700
P0303. C0040
P0305. C0035
P0401. C0055
P0404. B0024
P0463. B0026
U1016.

What should compression be on these motors?
 

012duramax4x4

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May 21, 2017
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I ran compression test on 1,3,5,7 and they were all around 350. So it's looking like it may be injectors but would this be the reaso I was getting fuel in my oil??
 

torqued2dmax

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Mar 26, 2017
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Brookville, PA
LLYs are known to rub through the fuel injection wiring harness in a several places ,do ice pick and check harness . That may be why the rates on some are off the chart . Just a thought , maybe an expert will chime in !
 

012duramax4x4

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May 21, 2017
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Who ever had the truck obviously knew about this because there was a ton of tape a wire loom around the harness by the Alternator bracket. I checked the wires there and everything looked good. Is there a way to use a bolt meter to check wiring at injector while it's running? What would I be looking
For?
 

012duramax4x4

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May 21, 2017
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Since I'm using dash command on my phone, has there been any problems with cylinder not matching with what the app is telling you? I'm assuming it's right since I was getting a code for misfire in 3 and 5. Also as the truck was idling I messed around with unplugging injectors I can unplug 3,5 and it makes a difference in the way the truck runs. When I unplugged 7 the truck fell down nearly all the way in rpm's and died before I could get to the ignition.
 
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joshd472

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Oct 10, 2016
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That's what I use to check my balance rates, works fine. When I had this problem I couldn't get a hold of a compression tester so I swapped the 1 and 3 injectors and the problem followed the injector. You could do this to rule out an electric problem.
 

012duramax4x4

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May 21, 2017
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Ok I was thinking about doing this but didn't know if I would need new o rings or anything because I don't have any.
 

joshd472

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Oct 10, 2016
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You will need new orings and crush washer. I got mine from auto zone for cheap
 

012duramax4x4

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May 21, 2017
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Ok I just changed #3 injector with #7 and the problem stayed with #3. I'm know thinking it is the wiring. How can I check this?!
 

2004LB7

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Dec 15, 2010
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I think the fcim will cut power to any injector it sees problems with. If there is a brake in the line or a bad connection at the injector it will likely do the same. You would need to make sure the connection is solid at the injector (ice pick) and then you can poke the insulation / wire with some needles and read the voltage with a VOM. I think it was 48 volts but it will be modulated or pulsed so it wouldn't look like 48 volts on the meter.
 

012duramax4x4

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May 21, 2017
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I have done the ice pick trick. I will check with a volt meter. I can't remember if I said before but once warmed up it smokes really bad like a stuck injector. Ughh this truck is a headache!!
 

kubitza123

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Sep 19, 2016
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Texas
I'd run it through an auction and let someone else worry with it. If no oil pressure after changing the oil the bearings are prob shit. Sounds like seller put the screws to you.
 

012duramax4x4

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May 21, 2017
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It has oil pressure I think it was problem with the stepper motor. I only paid a $1000 for the truck I think I'm way ahead
 

012duramax4x4

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May 21, 2017
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I checked the voltage on #3 injector I was getting 6.1 on wire and 6.3 on the other. I checked #2 injector that is showing good balance rates and I read 5.9 on both wires. I also cleaned the MAF as I read this could cause problems but no luck.
 

012duramax4x4

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May 21, 2017
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I figured out the problem. Someone had #3 and # 5 injector wires crossed. I was just messing around and seen that the one plugged into 3 ran all the way back in the harness with #7 so I swapped them and it's running like new with balance rates in spec! #5 had been cut and spliced before