6.4 boost/mileage question

footlong70 · Dec 30, 2014

Wish I could help you more with testing the vgt but I haven't played with them much. And I don't get that parameter to monitor on my blackmaxx. I know they do fail occasionally or get stuck. If it cycles though freely by hand, fully and springs back by it self then it's not stuck. So unless linkage inside the turbo let go/loose it's probably the solenoid. Is the plug clean and fully pushed in? Do you have access to another solenoid you could swap out and test? I'm sure someone has some tips on testing them.
Everything on the bp sensor/tube side sounds good to go.

08Monster · Dec 30, 2014

I could probably get one to try

08Monster · Jan 2, 2015

Well, I fixed the problem. I changed oil today, went for a drive, and no more issues.... Haha I have no idea. We will see how long it lasts.

footlong70 · Jan 2, 2015

???????????????????????????? lol

08Monster · Jan 2, 2015

I'm kinda thinking the same thing.... I'm just lost... Haha

Radioflyer · Jan 3, 2015

Anymore update on this Ethan?

The oil change fix still confuses the crap outta me..

footlong70 · Jan 3, 2015

I'm sure its coincidence. Are you sure its not a frozen tube? Just sounds so random. Do you park it some where warm every night? Or just when you did the oil change?

08Monster · Jan 5, 2015

Nope, its been outside and about +10 to -15 outside, I changed the oil outside too. Not a frozen tube, a new one at ford was like 6 bucks so I bought one. Boost has seemed normal the last few days and its been COLD. Didn't get above -7 yesterday.

footlong70 · Jan 5, 2015

weird.

08Monster · Jan 5, 2015

Issue is back today. Haha idk where to turn now.

footlong70 · Jan 6, 2015

A single lol?

08Monster · Jan 6, 2015

Thats exactly what I was thing. Give me my refund uncle Sam!!!!!! Lol that my first purchase.

08Monster · Jan 12, 2015

New issue. I barely tap the pedal and my boost shoots to 61lbs. My god.... As soon as it starts building boost on a hill, it doesn't quit building till I hit the brake to stop it. It goes from 15 and steadily raises to 50+ in a matter of 2 seconds with no change in throttle position. I have to hit the brake on every hill or it just spools the **** outta the turbos and doesn't let them unspool, even down hill

08Monster · Jan 12, 2015

Edit: bad link

08Monster · Jan 12, 2015

08Monster · Jan 12, 2015

As long as I stop the turbos from over spooling and I ease into the throttle I have normal boost at cruising speeds. Until the next hill where it slowly over speed them with linear throttle input. If I don't hit the brake it spoils them to 60 psi

footlong70 · Jan 12, 2015

Wow lol thats a new one... Can you hear the turbos? Are they actually spooling loudly? You can hear stockers when they are legitimately making 60 pounds of boost. The reason I ask is maybe your boost sensor is F***ed. Or wiring that is loose or shorting... So your boost is never actually that high or increasing uncontrollably. To build that much boost in such little time tells me it's not actually that high.
You also said that it keeps building boost, over spooling the turbos with your foot off the gas until you hit the brake?? If so that's a bigger issue.
The only other thing I can think of off hand is if for some reason the motor is actually making that ridiculous about of boost with no change in throttle position while climbing hill ect, would be the vanes randomly closing suddenly when they shouldn't. Having plenty of exhaust flowing to spool the vgt at say 50% or less position then suddenly closing without a decreasing exhaust flow, spiking the pressure. Which would go back to the original issue of wiring, sensors, or the vgt actuator is bad. What is your back pressure reading when you hit 50-60 psi? It should be maxed out pretty well at ~85psi. If Its not even close then that is a problem. Have you got a chance to try a different actuator?
Just out of curiosity when you drive and it's over boosting, does the exhaust appear more steamy than usual. Basically white exhaust which is common with over boosting due to vgt issues. Running lean...

B585Ford · Jan 12, 2015

Along the lines of what Footlong is saying, I am guessing you aren't making that much boost. If you are going down a hill at 1500 Rpm you would be lucky to max at 40 boost. You really need to monitor EBP when this going on. Unless there is some secret that I am not aware of your EBP will have to be pretty close to 60 (probably the 50s actual at the very minimum) to make 60 boost.

Radioflyer · Jan 13, 2015

B585Ford said:
Along the lines of what Footlong is saying, I am guessing you aren't making that much boost. If you are going down a hill at 1500 Rpm you would be lucky to max at 40 boost. You really need to monitor EBP when this going on. Unless there is some secret that I am not aware of your EBP will have to be pretty close to 60 (probably the 50s actual at the very minimum) to make 60 boost.

I'm gonna agree with B585 and Footlong,
Something doesn't seem right and if those chargers are indeed legitimately making that much boost, something is going to give. Aside from your oil leak you talked to me about Ethan, I'd start swapping sensors and see if that helps. EBP sensor is already scratched, that leaves two others that can be swapped from a truck that is known to not have issues. IF that doesn't resolve it, you know the number to call :thumbsup:

08Monster · Jan 13, 2015

Yes, you can hear them whistle and sounding like they are pushing hard. Yes, exhaust is white. It is also super doggy when the boost is high, the truck has no power at all. Today it was a true -21 without wind chill, so the sensor and tube might have been freezing up. Towards the end of my trip, I couldn't even maintain 55mph without my boost going and staying over 40psi. I was literally limping it on the highway. I swapped sensors, and its a no go. Issue is still there, it must be the VGT.