No boost to little boost

blpcjpblp · #1 (**permalink**) 01-08-2012, 10:29 AM

2005 6.0 48,000 miles. This truck sits alot in the garage. It does on occasion move in and out. A little history...always serviced at dealership..no problems until Aug 09...44,600 miles....low coolent and smell out the exhaust....replaced EGR cooler and complete service....no problems until Fri nite...pulled out of the garage, seems to run fine from stop light to stop light...went to merge on the highway, about got my a@@ ran over...no power and I thought I saw no boost on the gauge. Got off next exit...drove stop light to stop light and seems to run ok. Got back to the garage and check for the obvious and saw nothing wrong. Pulled the inlet hose off at turbo...spins smoothly by hand..no play in shaft...removed the EGR..a little sooty...not clogged...opens and closes smoothly by hand..put all back together...test drive....fine stop to stop...merge on highway, about got my a@@ ran over again....paid attention to gauge....maybe 5lbs of boost even at near WOT...no black smoke...back off of highway...seems fine from stop to stop....exhaust smeels a little "different"...maybe...ANY SUGGESTIONS

jesilvas · #2 (**permalink**) 01-08-2012, 11:00 AM

Bet your VGT is coked up and not moving. Or the solenoid is out. My bet is a dirty turbo, especially if it rarely gets driven.
and

Do some searching and reading, and you'll find lots on it.

**NYC F-350** · #3 (**permalink**) 01-08-2012, 11:23 AM

Quote:

Originally Posted by blpcjpblp

Got back to the garage and check for the obvious and saw nothing wrong. Pulled the inlet hose off at turbo...spins smoothly by hand..no play in shaft...removed the EGR..a little sooty...not clogged...opens and closes smoothly by hand..put all back together...test drive....fine stop to stop...merge on highway, about got my a@@ ran over again....paid attention to gauge....maybe 5lbs of boost even at near WOT...no black smoke...back off of highway...seems fine from stop to stop....exhaust smeels a little "different"...maybe...ANY SUGGESTIONS

A few other things that can contribute to low/no boost that you could check:
The ebp sensor and tube.
On your 05, the sensor is located on the drivers side, attached to the FICM bracket. Use two wrenches (one on the sensor, one on the tube) and remove the sensor. Take a long piece of tiewire or something similar and poke all the way down the tube to the exhaust manifold. There is nothing in there that you could possibly hurt, you want to make sure that the tube is not clogged with soot. Wipe the soot off the sensor and reinstall.

The MAP sensor hose and nipple.
The MAP sensor is located on the passenger side of the engine bay, on top of the heater box, attached to a triangular shaped bracket. Check the black rubber hose that goes from the sensor down to the intake manifold for any cracking, pinholes or chafing. Using an allen wrench close to the same diameter of the hole in the brass nipple the hose connects to on the intake manifold, poke the nipple to ensure that it is not clogged with soot.

If these do not help the situation, the fact that the truck sits long periods of time without being used points to the turbo sticking due to rust build up. The rust formation on the surface that the unison ring slides on prevents the VGT solenoid from opening/closing the vanes fully. You will have to remove the turbo and clean it.
To do so, I have included a link to a turbo removal/install pdf file. You will also need to purchase a turbo hardware kit, and a turbo cleaning kit.
Turbo removal/install CLICK HERE
Turbo cleaning directions CLICK HERE
Turbo cleaning kit, $57.20 CLICK HERE
Turbo mounting hardware kit, $7.70 CLICK HERE

Suggested upgraded parts to consider changing to ensure better oil delivery and draining for the turbo:
Updated turbo oil supply line, $77.00 CLICK HERE
Updated turbo oil drain tube, $21.45 CLICK HERE

blpcjpblp · #4 (**permalink**) 01-08-2012, 05:31 PM

I'll get started this week and let you know what I find. Thanks

michaelaiman · #5 (**permalink**) 01-09-2012, 02:04 PM

Its bad for these trucks to sit because of the VGT. long story short moisture in the exhaust causes the VGT to rust ans seize

Welder361 · #6 (**permalink**) 01-10-2012, 08:37 AM

I'm haven the same problem no boost replace map and cleaned hose and nipple replaced bp and cleaned tube took turbo off it was stuck cleaned it up and replaced unison ring the rod wore a groove on it took vgt off it was stuck could not push on it with my thumb so soaked it in some cleaner good as new put it back still nothing trying to figure out what it is any suggestion