lbz boost or sensor issue

[DIESELMAFIAPER.LB7]

K so I have this guy who says he's making 21 lbs off idle till his truck warms up. I thought sticky vains so I told him when it does it again take a pic of what vain position is when it does this.
The pic is at high idle bout -10 right now is it a sensor issue? It's not done till it got this cold or is the Cts just reading desired and not actual?

 

[Cknight199]

K so I have this guy who says he's making 21 lbs off idle till his truck warms up. I thought sticky vains so I told him when it does it again take a pic of what vain position is when it does this.
The pic is at high idle bout -10 right now is it a sensor issue? It's not done till it got this cold or is the Cts just reading desired and not actual?

Well I would say it's a sensor issue, maybe the boost pressure sensor (iirc it's in the intake runners) or wherever the trucks read boost from I can't remember. (Maf?) Is it even possible to make that much boost with 9% vane position at 1100 rpm?

 

[DIESELMAFIAPER.LB7]

Well im wondering if the vain sensor is reading wrong and it's impossible to make 20 lbs with 9% vain at idle if the vains are stuck closed I could see it and makes sense to me but if the vains aren't sticky then the map sensor is reading wrong when it's cold

 

[Cknight199]

Well im wondering if the vain sensor is reading wrong and it's impossible to make 20 lbs with 9% vain at idle if the vains are stuck closed I could see it and makes sense to me but if the vains aren't sticky then the map sensor is reading wrong when it's cold

Easiest way to tell if its reading right would be to listen to the exhaust and see if the vanes sweep at startup and if the continue to hiss or if it's a rumble. Or does it whistle a lot?

 

[DIESELMAFIAPER.LB7]

I haven't seen the truck there bringing it now I asked them that and they just went huh? Lol do I'll let it sit and get cold start and log vain position and map and boost and maf see what's going on only code they say they get is p0108 which is a bar mismatch iirc so no vain codes

 

[Cknight199]

I haven't seen the truck there bringing it now I asked them that and they just went huh? Lol do I'll let it sit and get cold start and log vain position and map and boost and maf see what's going on only code they say they get is p0108 which is a bar mismatch iirc so no vain codes

Gotcha sounds good let us know :thumb

 

[baggedLB7]

I wouldnt think that even with the vanes closed at just an ideal at that rpm there would be enough load on the turbo to get anywere nere 20lbs of boost.

 

[Cknight199]

I wouldnt think that even with the vanes closed at just an ideal at that rpm there would be enough load on the turbo to get anywere nere 20lbs of boost.

X2 my thoughts exactly

 

[plowboy_lbz]

The only real way to confirm this would be to put a manual gauge on it and compare. Also you said it does it until the truck warms up, in your pic the edge shows 170 deg. I would consider that warm. How does the truck perform driving?

 

[DIESELMAFIAPER.LB7]

No idea on how it drives yet he claims it slams 38 psi really quick but after 180* it stops but it doesn't always do it when cold either so.... I wouldn't think it could hit 20 psi stuck closed but I sure as hell know it can't with vains wide open so being stuck makes a "little" more sense but that's why I also think there is a sensor issue somewhere. I'll take one of the plugs outta the egr delete and put a guage in and see what it reads like stated that will tell the issue

 

[DIESELMAFIAPER.LB7]

Well im pretty damn sure this is a wiring/sensors issue I got it to hit 52 psi at 3 mph :rofl: so now it's a matter of tracking some wired around see if there is anything shorting or messed up if not I'm going to swap the map sensor.

Kinda odd it will only do this cold but not always when it's cold never when it's warm got p0106 map sensor high circuit code just now to

 

[DIESELMAFIAPER.LB7]

well I forgot to hit log the one time it messed up I logged it 3 times after never skipped a beat ran perfect checked wiring looked fine so guess we'll try getting a new sensor swap it see if it repeats the issue.

cant get the logs to load.....