2005 6.0 slight miss no codes power balance ok

ClassicIDI

Member
Joined
Jun 16, 2011
Messages
137
Reaction score
0
Location
CO
ok I'll try to make this short but Ive stumped 3 other techs around my town thus far with this truck.

Truck is a 2005 with 260k on it. original owner and impeccably maintained. Came in to have head gaskets done only as a preventative measure due to miles. Started and ran great before work was started, hot or cold. injectors were done 60k ago so owner decided to re-oring them and put them back in.

Tore the truck down and everything looked great. Put new heads on from UCF, ARP's, bullet proof water pump, bullet proof fan clutch adapter, new ford gasket's/ orings, glow plugs/harness's. noticed one injector missing fuel inlet screen so I replaced that injector which is now in #2

Truck already had bullet proof egr and oil cooler, & FICM so those were reused.

Installed a powermaxx stage 1 during reassembly.

Truck is now back together and running again but has a very slight miss. it starts hot or cold without hesitation. I have driven it roughly 30-40 miles since the work and the miss is staying the same. It idles smooth but if you rev it in park you can feel it in the steering wheel. just a slight da-da-da-da.

driving the truck WOT it runs great and is smooth however trying to maintain a speed at aprox 65-70 at 1800rpm the whole truck shakes and can be felt in the seat and wheel. mash the throttle and it smooths out.

tried swapping FICM's with no change. hooked up to IDS and ran power balence with no real conclusive result. 1,2,7,3 are +10 and 4,5,6,8 are -10

here is a video of the test. first at idle then rev in park and then a power brake. all with adaptive turned off. also passed relative compression and engine sounds normal cranking over, no speed up points.

th_VID_20170112_104711166_zpskxvkdnac.png
 

sootie

Well-known member
Joined
Oct 3, 2012
Messages
11,854
Reaction score
30
What is fuel pressure and what is icp when this is occurring .

I wouldn't rule out injectors personally...
 

kwelch08

New member
Joined
Apr 21, 2014
Messages
511
Reaction score
0
Location
corpus christi TX
What is fuel pressure and what is icp when this is occurring .

I wouldn't rule out injectors personally...



+1 on the injectors. Also check the wiring harness going to the injectors from the ficm mine was doing the same thing and I had a crushed set of wires, and after I changed out the ficm harness and it completely fixed the problem


Sent from my iPhone using Tapatalk
 

ClassicIDI

Member
Joined
Jun 16, 2011
Messages
137
Reaction score
0
Location
CO
fuel pressure is 54 at idle and when reved up where i can feel the miss the needle jumps a few psi but stays 51-55. icp idles around 700 and .95 volts ipr is 23% at idle when reved up and held at the "miss" rpm icp is 770 and 1.05 volts and stay consistent. ipr goes up a few %.

im not able to drive the truck right now since ive now moved on to some axle work. this is all done with the truck standing still
 

IIVonnyII

New member
Joined
Dec 12, 2016
Messages
65
Reaction score
0
Location
Langley, BC , Canada
not to question your mechanical capabilities, but is there any chance you could have pinched an injector o ring during installation? what you're experiencing suggests injector issue to me, and if it was working properly before .. on paper it should work properly after. just my experience with these beasts
 

ClassicIDI

Member
Joined
Jun 16, 2011
Messages
137
Reaction score
0
Location
CO
Anything is possible. I'm very careful about those kinds of things normally. I bought a new ficm harness and am going to try that. But if not then I'm pulling all the injectors for inspection. I'm just baffled how they went bad sitting on a shelf the oring thing makes sense.
 

Members online

No members online now.
Top