Boost pressure control valve

[V10 SPM]

Is it possible to tell whether the boost pressure control valve is functioning? What symptoms would be noticeable if the valve has failed?

[stevieturbo]

V10 SPM said:

Is it possible to tell whether the boost pressure control valve is functioning? What symptoms would be noticeable if the valve has failed?

Yes...and if it wasnt, boost control would not be working correctly.

[anonymous-user]

V10 SPM said:

Is it possible to tell whether the boost pressure control valve is functioning? What symptoms would be noticeable if the valve has failed?

Simple. Identify the input (usually a pressure line from either the compressor housing or the plenum) and the Output (the line to the wastegate capsule) and link them straight together without the valve in the middle. This will give a level of boost called the "minimum boost line" because it is equivalent to the valve doing no venting. If the valve is working, you should notice a lot lower performance on the min boost line than with it working to increase boost.

A "Braver" test is to remove the valve and block the input feed, which will be the "maximum boost line" equivalent to the valve dumping all actuation pressure overboard. In reality, most valves cannot truely get to this level of dumping, and care is needed because the engine can overboost (which on a modern engine should be caught by the overboost limiter) but it will demonstrate that the turbo and the rest of the system is functioning correctly