I am going to try to keep this short while still explaining everything..

I bought the truck a year ago, it has run great until last fall while towing very heavy, I would get a CEL and underboost code. It would only do it up hills while towing over 11k pounds.

It eventually got more common and would do it while towing anything under heavy acceleration or hills. I would just reset it and go on my way. I would always still see 28-29 lbs of boost under WOT or towing.

So basically about a week ago it wouldnt go over 22 pounds of boost no matter what. and I would get the codes. I just had some bulletproofing done and had everything gone through and the turbo completely cleaned. The shop said it was very dirty and the unison ring was frozen.

Now it runs much much better and I am not getting any codes, but it still will not go over 21-22 pounds. Down low I can feel the turbo kicking in much sooner and the truck feels much stronger overall, but still doesnt have the high end pull that it did when I bought the truck.

What would make the truck be limited to 21 pounds of boost but yet not throw any codes? he checked the uppipes and everything and said they are not leaking.

I appreciate all the help you guys have given me so far!

 

I did lots of searching but couldnt find anyone who stuck with the thread long enough to give what the root of the cause was..

 

oh and I am also lately getting a long cranking time intermittently.. it is very random and it will just sit there and crank for almost 10 seconds and then fire up and run perfectly.. not sure if this is connected or not but figured i would throw it out there.

I read a thread that said to check the ICP and it is in the high 500's idling, and about 3900 WOT

 

anyone have an idea of what i can check? i have a cts and very little knowledge of what to check..

 

Do you have any gauges???

 

Opps CTS

At KOEO Check
BARO
MAP
EBP
ICPV
IPR%
At Hot Idle check
BARO
MAP
EBP
VGT%
ICP
IPR%
2500rpm check
BARO
MAP
EBP
VGT%
ICP
IPR%

 

STart truck Cold feel around all turbo connections

You can also get a Cap deal with a Valve stem to put on the turbo Cold side Inlet and then Air test the Intake system for Leaks

The cap deal can be found at like a Home Depot plumbing area

 

thank you so much. i am checking them at the moment. i found all but ipr... what is that?

 

IPR is the valve that controls the PSI of HPO

Its a Vwery Important one to get as well


You will need to go to the Edge website and Update your Unit to get IPR% Gauge its a Newer gauge that edge just added awhile back

 

KOEO




2500 rpms


hot idle

 

your EBP Sensor is the PROBLEM

Try Cleaning ebp sensor and Tube

Replace if Clean don't work

 

At KOEO ALL Pressure sensor should read SAME as Baro

BARO--MAP--EBP are ALL Pressure sensors

BARO sets the Baseline

 

WOW thanks for the help! I am glad I found out what it is. I just had a shop work on it and he said he cleaned the EBP tube, so I am assuming that it will need to be replaced. Any links to a few pictures of how to do this? I am a visual learner..


I did notice while doing what you said and checking around the truck after start up and I noticed there was almost like an air leaking sound coming from around the FICM area.. Not sure if it is normal or not or really how to describe it, hard to hear over the engine.

 

I didnt realize the EBP sensor worked like that, it has been that low for a while..

 

Really air leak sound

The EBP is right next to FICM

Maybe the guy left it Loose and it leaks when running, However Leak or not it still should still report same as BARO at KOEO



there a slim chance you can clean EBP Sensor andtube to fix kinda sounds like its been tried so IDK

probably need to replace the EBP Sensor in all honesty