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 2004 amtran VT365 -6.0 crank no start
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td083
Senior Member

192 Posts

Posted - 06/25/2020 :  10:22:34 AM  Show Profile  Visit td083's Homepage  Reply with Quote
hey all i have a 6.0 came in for unrelated adjustements and broke down in my bay
-the bus cranks wont start when it first happened it cranked seemed to start and cut off after couple seconds now cranks and wont start
its throwing dtc 147 & 143 codes and 147 is setting just before 143 crank and cam dtcs
--i have changed both cam and crank sensors and connectors with pigtails ,i ohmed out and load tested circuits for both the cam and crank from the ecm
--i swapped out a ecm with sister bus , i removed crank sensor and visually checked teeth looked fine upon inspection ,the batt voltage is good as well
-on the trouble tree it lists electrical interference in circuits ?i also checked there are no trans dtcs as well
--NO rpm shows up on the guage i double checked new sensors , im wondering could it be out of time somehow although was running ok and cranks normally as well the cranking compression test comes up looking normal ,pulling my hair out on this one any input greatly appreciated thanks

Edited by - td083 on 06/25/2020 10:23:03 AM

Bluenozer
Advanced Member

Canada
342 Posts

Posted - 06/26/2020 :  01:50:53 AM  Show Profile  Reply with Quote
remove your crank sensor, where it seats take a small hammer and punch and tap there, you will see flake rust pop off( just make sure it is clean and has a goood base) reinstall sensor , seen alot of times just one little flake( you what cast does) will cause a crank code, sitting inside it swelled and made the gap to large for the hall effect sensor

OEM trained in wiring and all engine platforms for 20 years

Edited by - Bluenozer on 06/26/2020 01:51:41 AM
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td083
Senior Member

192 Posts

Posted - 06/26/2020 :  08:29:57 AM  Show Profile  Visit td083's Homepage  Reply with Quote
thanks yea true i have had that happen ,so i did check the seating areas yesterday and tried to wipe clean didnt see and bubbled up rust or paint looked good its a couple year old jasper
- today checked both when cranking getting millivolts from both , our next step is to scope the sensors and check patters other than that thinking internal issue and have to go from there , evening shift guy went behind me last nigh t and checked out as well and had no answers at this point either .i will update with conclusion ,
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ParklandGarage
New Member

1 Posts

Posted - 07/10/2020 :  08:22:48 AM  Show Profile  Visit ParklandGarage's Homepage  Reply with Quote
Did you find anything? I have one exact same issue, did all tests everything seems good.


quote:
Originally posted by td083

thanks yea true i have had that happen ,so i did check the seating areas yesterday and tried to wipe clean didnt see and bubbled up rust or paint looked good its a couple year old jasper
- today checked both when cranking getting millivolts from both , our next step is to scope the sensors and check patters other than that thinking internal issue and have to go from there , evening shift guy went behind me last nigh t and checked out as well and had no answers at this point either .i will update with conclusion ,

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td083
Senior Member

192 Posts

Posted - 07/10/2020 :  10:34:07 AM  Show Profile  Visit td083's Homepage  Reply with Quote
well we ended up scoping the cam and crank sensors , the graphs looked fine so we ended up determining it must be internal issue and the engine was a jasper reman only 2years old or so ,so it should be covered under warranty , we sent it out to where it was installed at the time , we used to send out engine jobs so we havent heard anything from the shop yet, they seem to take their sweet time when i know something on the consensus from them i will post but it could be a while .Its an odd one for sure because i know the ecm is good the circuit is good and the sensors are reading correct , and it didnt sound abnormal when cranking or anything . i went out for a drive after some unrelated small repairs came back and went to park the bus because i was done with it and thats when it wouldnt start .

Edited by - td083 on 07/10/2020 10:38:43 AM
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td083
Senior Member

192 Posts

Posted - 07/10/2020 :  10:40:17 AM  Show Profile  Visit td083's Homepage  Reply with Quote
is yours throwing the same dtcs with the same issue ?
quote:
Originally posted by ParklandGarage

Did you find anything? I have one exact same issue, did all tests everything seems good.


quote:
Originally posted by td083

thanks yea true i have had that happen ,so i did check the seating areas yesterday and tried to wipe clean didnt see and bubbled up rust or paint looked good its a couple year old jasper
- today checked both when cranking getting millivolts from both , our next step is to scope the sensors and check patters other than that thinking internal issue and have to go from there , evening shift guy went behind me last nigh t and checked out as well and had no answers at this point either .i will update with conclusion ,



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