I've searched plenty, but can't find anyone actually talking about doing a boost leak test. Others have asked, but none have reported actually doing it (except testing the intercooler). Has anyone done one on the CRD? Anything to look out for when pressurizing the system? Planning to either pressurize at the inlet to the turbo/intercooler hose or before the turbo. Will take out the oil cap as well, just need to know if there's any danger to the oil system or if popping the oil cap will cover it.

Reason for boost leak test: pulled the FCV/intake elbow to cap the EGR cooler lines in an attempt to figure out a small coolant loss. I recall seeing closer to 20psi on torque, now I am only getting to 16psi that tapers off pretty fast. GDE eco tune is supposed to hold 20psi over ambient up to 3800rpm, and that is not what I'm getting. Also, getting what can only be described as air-cooled VW air whistle when boosting. This is in addition to the normal turbo sound.

With the OEM calibration, you'll find that peak boost is a pressure ratio of 2.335 bar respective to atmosphere at 2200rpm. On a boost gauge, you would see: (2.335bar - 1 bar (atm) ) * 14.7 psi/bar = 19.6245psi. In a transient maneuver you might see it spike up higher quickly, but in steady state conditions 20psi would be the max. However, at RPM climbs above 2200rpm, the boost setpoint falls off quickly, and by 3800rpm you're down to a 2.24 pressure ratio / 18.228psi.

With the GDE Eco-performance tune and the turbocharger at maximum speed limits, we have a boost setpoint that holds a 2.4 pressure ratio / 20 psi all the way from 1800rpm to 3800rpm. However, the real change is in the normal driving range where you'll see an increase, in some areas, of 5-6psi or higher.

There was never any changes to the boost setpoint that would've had customers seeing 26psi on a boost gauge - if they were, it would've been in a transient maneuver where the closed-loop boost governing wasn't reacting fast enough and allowed for an overshoot of the boost setpoint (most likely in first gear during a WOT).

I'm in colorado, so at altitude. Here's where I got the info:



http://www.greendieselengineering.com/j ... ist/7.page

Most boost leaks you can hear. (like a "whoosh" or a "whistle")
A serious boost leak will cause a P0299 underboost code.

What boost level does torquepro display with the key-on engine-off?
Typically, when you are at a high altitude, it will be a negative number.

I'd go back and make sure that your intake elbow and EGR connections are bolted down tight.

Maybe you forgot to put a gasket in?

If your EGR is still connected, maybe its stuck open and allowing boost to escape out the exhaust.

I too suspected a minor boost leak based on torque pro readings...but as of yet have not found any leaks. My torque pro app shows a brief peak boost of around 21 and holds steady around 18-19 psi during a full throttle run. This is with a GDE ECO FT tune at 1000 feet MSL.
My EGR is removed and blocked off. New MAP sensor (the cheap Bosch one). Turbo actuator vacuum and rod are all operating correctly. Smoke on hard acceleration is minimal. Stock tires and ride height and I get about 27-28 mpg on highway at ~70mph.

I definitely thought about blocking off the EGR, but decided not to after reading that GDE uses the EGR valve as a type of turbo dump valve. Then I came to the realization that diesel's don't really need a blow off valve. I may go back to do that.

I definitely thought about blocking off the EGR, but decided not to after reading that GDE uses the EGR valve as a type of turbo dump valve. Then I came to the realization that diesel's don't really need a blow off valve. I may go back to do that.