2005 6.0 won't idle.

DZL JIM

Member
Joined
May 18, 2011
Messages
913
Reaction score
0
Location
North East Ohio
Got a 2005 6.0 customer's truck here we are totally stumped with and I need some outside, fresh input what to look at.
We replaced 4 injectors and the oil pan for the customer. Afterward we fired up the truck and it won't idle. You have to feather the throttle to get it to fire, and you can hold it around 825 rpm and it runs great, will rev and run fine above that.
It fires and instantly dies, unless you feather the throttle to keep it running.
When it is running as soon as you let off the throttle it dies.
We have no idea if it was an existing condition or not as all 4 injectors were dead when it was delivered and you had to be aggressive with the throttle to make it run anyway.
Cam sensor code keeps coming back.
We replaced the ECM twice, swapped in a reman FICM, swapped in 2 different crank sensors, 2 different cam sensors, new IPR.
Unplugged the throttle pedal and even swapped it with another one.
Nothing we have done will make it idle.
I have unplugged every sensor not critical for firing and idling with no change, with the exception that when I unplug the Exhaust Back Pressure Sensor it will fire and idle for exactly 2 seconds then die.
The turbo test checks out with good Baro, MAP and EBP all matching at 14.
I datalogged the event when it dies with IDS watching ICP and IPR duty cycle. Both ICP and DC don't change until rpm's reach around 500 rpm (drop from 825), so I really don't think it's a High Pressure Oil issue --causing-- it to die.

We can't be the only one to run into this.
Any help or direction is greatly appreciated.

EDIT: Low pressure oil is perfect at all times at 60 psi. Fuel pressure is solid at all times at 55 psi. Fuel filters are new, as is engine oil and filter (new oil pan).
 
Last edited:

DZL JIM

Member
Joined
May 18, 2011
Messages
913
Reaction score
0
Location
North East Ohio
Forgot to mention we did the pigtail.
Not sure how to load test that circuit....??

EDIT: We checked continuity from sensor to the ECM and all was good, if that's what you mean.
 

DEEZUZ

NO PUKESTERS
Joined
Jun 30, 2011
Messages
6,857
Reaction score
194
Location
NWI
At anytime you swapped cam and crank sensors, did you inspect tone ring while cranking?
 

DZL JIM

Member
Joined
May 18, 2011
Messages
913
Reaction score
0
Location
North East Ohio
Did not look at tone ring. What do we look for exactly?

Did not do air test because it fires right up with oil temps at 190°.

How can there be an issue with the tone ring if it fires up perfectly and runs perfectly, as long as you hold it above 800 rpm?
I would think a tone ring issue would not allow it to fire at all....?
 
Last edited:

DZL JIM

Member
Joined
May 18, 2011
Messages
913
Reaction score
0
Location
North East Ohio
After literally days of searching the web, I found a thread from last year, guy had the same issue, said it was rust behind the CMP sensor. My tech spent hours getting the original one out because of rust. We will go back in and clean that surface up super good and see what happens.
 

DEEZUZ

NO PUKESTERS
Joined
Jun 30, 2011
Messages
6,857
Reaction score
194
Location
NWI
Yes, rust jacking. The new sensor mounting surface may already be distorted.

As far as the tone ring, there is always possibility of crank walk.
 

DZL JIM

Member
Joined
May 18, 2011
Messages
913
Reaction score
0
Location
North East Ohio
Bingo, got it.
If my tech would have done his job correctly in the first place and cleaned the CMP sensor surface like he was supposed to, it would have saved me 2 1/2 days in labor chasing this thing.
Incidentally, that same tech was let go last Friday for many reasons, some of which apparently we are still dealing with...

Thanks for the tips all, greatly appreciated.
 

06Amarillo

New member
Joined
Oct 13, 2016
Messages
59
Reaction score
0
Great bunch of guys on the forum that's for sure !! Complete strangers helping some out out.
 

Latest posts

Members online

No members online now.
Top