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ECM bad or sensor or wiring issue


Cjchap

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We have been at this truck for weeks now. I bought it about 3months ago and it just sounded like it needed new injectors. In the last 3weeks we have replaced the injectors 3 times because it keeps sounding the same. Its a constant misfire whether at idle or acceleration. I pulled the codes with my scan tool and its giving codes p0193, p0113, p0237, p0069, p0483. Also it says fuel rail pressure relative to map.  We have checked over and tested the wiring harnesses and this is what we have come up (truck in run position) the fan has 5volts, the cam black/blue 35ohms tan/yellow 5.1v grey/black millivolts, map sen shows 5volts on feed wire the ground was within specs but the signal wire had 5.1volts.

Is the signal wire supposed to have 5v @ map sensor and is the signal wire to cam sensor supposed to have 5v to?

Any ideas I will appreciate. I'm at a loss right now.

It is a 07 5.9 Cummins

Thanks

Edited by Cjchap
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The first thing I think of when I see that many codes is something is shorting out causing the sensors to go wacko.  

 

I would test each sesnor for a short etc.  

 

I know when I had an oil pressure sensor shortout internally it caused a ton of codes and weird issues.

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I have tried to find the values of resistance for the map and can sensor and can't find anywhere. On my scanner the map is showing 29.6 and fuel rail is bouncing between 20 and 50lbs. This is with the key in the on position not cranked over.

Is there supposed to be 5v on signal wire for map and cam sensor?

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I think all sensors should use 5v input.  I would test for shorts to ground from the input v and output wires on the sensors.   

 

map will read 29 at idle as it reports boost in InHG, so at 29 you get ~14 PSI which is about what atmospheric is at sea level.

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OK. Now a further issue after testing the fuse panel. I pulled fuses one at a time and tested. When I got to pcm engine management socket both sides tested hot. One side tested 11.7v and the other side tested 12.3v. Is this supposed to be like this? Like a dual power for one source? Any ideas would be great. 

Thanks

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Thanks for that. I was worried that my radio antenna did something to it. Where I park it my wires are 50ft in air above it. Do you know if its surface mounted diodes and resistors inside the ECM? It is opening day so I went hunting instead of pulling it early this morn. I needed to chill for a minue. I'm about ready to pull my hair out over this.

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Thank you for that diagram. I was just reading about your test for the alternator. I'm going to do that in the morning. I did order a new ECM just in case. Weird thing too is check engine light has never been on once during this.

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