Boost problems!!!! NEED HELP!!!!

Foggy6.0Liter · Sep 22, 2015

Okay guys, been tearing my hair out over this issue for quite while. I can't get the truck to make the boost it should and its been getting worse. Peaking at 22psi, I'm running a barder stage 4 71mm powermax and 275/100s, truck should make 40+ pretty easily. Thus far I have checked for exhaust leaks and intake tract leaks, no issues, (pressurized the intake tract with shop air and sprayed it down with soapy water). Replaced map sensor and hose, replaced ebp sensor and tube. Tried running with map sensors unplugged, tried with vgt solenoid unplugged. Swapped out the stage 4 for my stock turbo, no improvement after any of these efforts, actually running worse now with the stock turbo. Boost peaks at 13 with the stock turbo. Only known issue with the truck is I know the head gaskets are compromised, but I wanna get this boost issue figured out before I tear it down to do gaskets. Any help is appreciated.

Foggy6.0Liter · Sep 23, 2015

No help guys??

Powerstroke Man 6.4 · Sep 23, 2015

Foggy6.0Liter said:
No help guys??

What tuning are you running? did you check the uppipes is the truck smoking a bunch when trying to get up to speed? any codes?

Extended Power · Sep 23, 2015

Everything from manifold to block leaks, manifold to up pipe leaks, up pipe bellows leaks, up pipe adaptor leaks....
Stock intercooler? Cracked tank ends?
Cracked or ripped silicone boots.
Open port not plugged on piping, or?

KCTurbos · Sep 23, 2015

Check for exhaust leaks.

Do you have an egr valve plugged in?

Stop replacing stuff and do a little diagnosis. You need to monitor ebp, map, maf, and vgt duty cycle and it should point you in the right direction.

Foggy6.0Liter · Sep 26, 2015

All this stuff is great guys but I'm beyond pretty much all of it. All my sensor data looks good. No boost leaks and no exhaust leaks, truck is always smokey/hazey (275/100) injectors. I have several tunes from good tuners, all act about the same. Intercooler is mishimoto, up pipes are one piece rcd, manifolds are BD, intercooler pipes are nolimit, boots and clamps are mishimoto. All parts have less than 4k miles on the. I have checked as I stated above, for exhaust and intake leaks.

KCTurbos · Sep 26, 2015

I work with Vgt turbos for a living. It is usually a leak or sensor issue. Can even be a chaffed wire.

Do you have you egr plugged in?

What do the following sensors read at wot?
Ebp
Boost
Maf
Vgt duty cycle

swinky · Sep 26, 2015

Just go ahead and get rid of the vgt and solve your problems. No vgt is going to keep up with 275/100s

Sent from my SM-N920P using Tapatalk

6.0 Tech · Sep 28, 2015

You didnt say what year it was, so i'm gonna guess here. I've seen throttle plates close on early models, check that i suppose. How are you measuring boost, mechqnical gauge or digital? I've seen kinks in mechanical gauge supply tubes cause low readings. Did you check the fitting on the intake for plugging when you replaced the map and hose? Any possibility you have a fuel pressure issue so that the turbo isn't actually spinning fast enough o build boost? Seen hi pressure oil issues do that too. As was stated before check all your pressure pids. Key on engine off the map, baro, and ebp should be within 1.5 psi of each other per ford, i like to see them much closer. Did you check the ebp connector when you replace the senso and tube? Seen plenty of those corrode. If its a late05 or later they like to chafe on the hose on yhe bottom of the degas too. Hope that'll help a little.

Foggy6.0Liter · Sep 28, 2015

Okay guys, so heres some answers to your questions. First off the truck is a late 05 so no throttle plate and no maf sensor, i also have no EGR on the truck, valve is out and blocked off.

Im using an electronic pressure sensor to read boost. I did not check the fitting at the time i changed the map hose, i will recheck it but its a stage 2 ported intake and i cleaned and checked all fittings when i installed the intake. I did check the harnesses and connectors for EBP, MAP and VGT, all looked good. As far as fuel pressure i set it at 70 and it never drops below 62-3 at WOT. ICP Voltage peaked at 4.7 so oil system should be in order.

At WOT
EBP peaked at 38.7 PSI
Boost from the Gauge sensor peaked at 19.8
Boost from the Map peaked at 28.7
I have no MAF sensor
VGT duty cycle ranges from 15ish% to 80% but my CTS2 doesnt show it in the data log stream so id have to make a pull to check it.

I can send any of you guys a copy of the datalog file if you wanna check it out.

KCTurbos · Sep 28, 2015

I know is sounds weird but I have had many customers that had similar problems that went away after plugging the egr valve back in. You can just let it dangle and don't have to install it into the manifold.

Do a quick run and read VGT duty cycle at WOT. That is the number we need to know.

matt92idi · Oct 5, 2015

Would not having a maf sensor have anything to do with it? I thought vgt turbos needed to have that in place

KCTurbos · Oct 5, 2015

Some trucks came with NO MAF from the factory... in that case you don't need one.

If you truck came with MAF from the factory... then depending on your strategy you need it for the vgt to cycle correctly.

Also for some reason... some strategies need an EGR valve plugged in electronically.

Foggy6.0Liter · Oct 13, 2015

Okay so i ran it with an EGR plugged in, noticed no change that is really significant, Kyle Blackstones tuning adjustments seemed to help some. I got boost to peak at 31. VGT % ranged from 45% when i rolled in to down around 22% at wot.

6.0 Tech · Oct 13, 2015

Is there a cat on the truck? Try unhooking the down pipe from the turbo and see what happens. Seen a plugged cat once, possible there are some other issue in the exhaust too i suppose. Wa the 31 psi on the stock turbo or back with your stage 4?

powerSmokin · Oct 14, 2015

Has this always been like this since the install of the injectors and turbo? Just sounds like the turbo isn't lighting all that well with the huge sticks, if the tuning tweaks made a change from 22psi to 31psi, i would say tuning is definetly a factor. Find someone that does live tuning in your area is always an option.

Foggy6.0Liter · Oct 16, 2015

Thanks again for the replys guys. first off the truck is fully strait piped, 4 inch down pipe to 5 inch into the stack. 31PSI was with the stage 4 back on it. I think tuning is the main issue, its always been light on power/boost since i did this setup like powerSmokin said. Unfortunately closest tuner would be in PA. I think things need to be adjusted better for the big sticks.