6L VGT Duty Cycle

[Storm]

I'm watching a log on a truck that's not pulling over 20lbs of boost at WOT..

idle - VGTDC .662

3000rpm - VGTDC .362




What's the ranges on VGTDC ?

 

[blacksnapon]

VGTDC # 0 73 43 0 - 100 percent duty cycle. KOEO.....0..Low idle..........73..high idle.........43.. range........0-100%

 

[Storm]

KOEO Low Idle are you saying .73
High Idle .43

?

 

[d-kuzmen]

When we view the VGT it's viewed in % ranging from 0-100% not in voltage.

Vgt should be at 85% WOT.
]



10 VGTC 12.1 7.9 10.4 0 - B+ Variable Geometry Turbo Actuator Control (Pulse Width Modulated


12.1 volts is KOEO 7.9 is Low idle 10.4 is high idle


Wish I could give better info..

 

[Storm]

Aye.. What the hell is SCT doing than with software.. I don't get why their VGTDC is misreading.. I assume its pulling the VGTDC from the same area ya'll are..

Hmmm

 

[d-kuzmen]

Aye.. What the hell is SCT doing than with software.. I don't get why their VGTDC is misreading.. I assume its pulling the VGTDC from the same area ya'll are..

Hmmm

Dunno, but if your only getting 20psi at WOT, couple things I would check, fuel filters (first) make sure egr isn't stuck open, then you could also pull the turbo and open it up to check if it's sticking. I can send you the TSB on opening it up if you want, lemme know..

 

[Storm]

I have that.. It's for a buddy who's about 200 miles from me.. He's trying to keep from going to Ford b/c he isn't comfortable with their service..

He asked me to look over this log, and I can see a problem.. He's a truck driver and sometimes the truck sits for weeks.. I'm thinking stuck vanes because it's not being ran..

 

[d-kuzmen]

I have that.. It's for a buddy who's about 200 miles from me.. He's trying to keep from going to Ford b/c he isn't comfortable with their service..

He asked me to look over this log, and I can see a problem.. He's a truck driver and sometimes the truck sits for weeks.. I'm thinking stuck vanes because it's not being ran..

Thats what happens. We tell our cust to drive'm like they stole'm!!

 

[Storm]

Exactly... The problem is, It appears the Duty Cycle isn't getting to the right place for the boost build.. It's like it stalls, however looking at it in current, its hard to decode it into actual Duty Cycle.. I may have to call SCT on this one and find out why the VGTDC PID is showing voltage.. I know its the same PID ya'll use, maybe ya'll software readjusts the signal into a different format..

 

[d-kuzmen]

Exactly... The problem is, It appears the Duty Cycle isn't getting to the right place for the boost build.. It's like it stalls, however looking at it in current, its hard to decode it into actual Duty Cycle.. I may have to call SCT on this one and find out why the VGTDC PID is showing voltage.. I know its the same PID ya'll use, maybe ya'll software readjusts the signal into a different format..

Thats possible but you need to remember just because the pid reads 85% or so there is no sure way to know the position of the VGT without out new fancy tool we have.

 

[Storm]

See I don't know what 85% is tho because what I see on VGTDC PID is decimal.. Unless we have a way to compare 85% to the decimal.. I could easily say .662 is 66.2%

LOL but than that doesn't make sure.. More boost you build the high the Duty Cycle goes right? or the lower?

 

[d-kuzmen]

See I don't know what 85% is tho because what I see on VGTDC PID is decimal.. Unless we have a way to compare 85% to the decimal.. I could easily say .662 is 66.2%

LOL but than that doesn't make sure.. More boost you build the high the Duty Cycle goes right? or the lower?

More duty cycle more boost. Correct

 

[suprdtydvr]

VGT position

Hey new to the board and was just reading along. Even with whatever readout of the signal that is being sent to position the VGT it is just that. You still have to parse out the actual position of the VGT as it may be stuck correct? As far as I gather there is no feedback signal to the computer that gives actual VGT position.

JR

 

[d-kuzmen]

Hey new to the board and was just reading along. Even with whatever readout of the signal that is being sent to position the VGT it is just that. You still have to parse out the actual position of the VGT as it may be stuck correct? As far as I gather there is no feedback signal to the computer that gives actual VGT position.

JR

You are correct there is no feedback to the pcm so it has no way to know correct postion. Welcome to the board, I see your from Preston CT im in Griswold.