Turbo Backpressure sensor and valve

[gofastpilot]

Besides for warming the engine up faster what is the reasoning for the backpressure valve? My Edge Evoulution in datastream mode is showing Turbo BP @ 15psi with the engine off!!!? No wonder I dont hear the turbo spool up. Any suggestions?/.........gofaspilot

 

[whatabudro]

Atmospheric pressure is 14.7 so 15 is zero follow?

 

[gofastpilot]

Shouldnt it be called in.hg. instead of psi?

 

[Fire1]

Shouldnt it be called in.hg. instead of psi?

Not unless you are reading negative pressure (vacuum).

 

[powerboatr]

Atmospheric pressure is 14.7 so 15 is zero follow?

bing bing bing
give that man a dollar,
funny your tuner reads 15 and not mm

budro is correct, send him beer.

 

[oi8228oi]

bing bing bing
give that man a dollar,
funny your tuner reads 15 and not mm

budro is correct, send him beer.

i woulda said the same thing so can i get a Shot as a runner up!

 

[gofastpilot]

Still didnt get a answer for the bp valve. Does gm and Cummins use it if so I'll accept it as poor engineering..........

 

[JOAT]

Only original purpose of the BP valve is faster warmups, something I've come to appreciate. I have mine manually activated, so I can choose when to use it, both for warmup and as an exhaust brake. The PCM only partially closes it, so it doesn't help alot. With the switch, I can close it all the way, and with the engine at 1200 RPM it is cranking out heat within a few minutes.

 

[Tx_Atty]

Joat, I read Baz's description of the exhaust brake and it says it isnt useful under 2000 rpm. At 70 mph Im only at about 2100 (3.55 gears). Is his description accurate or could I benefit? When my valve closes in winter even just putting around town I feel a really strong resistance.

Sorry to hijack.

 

[JOAT]

I find it fairly useful as an exhaust brake at down to about 1200 RPM, tho the effect diminishes as RPM lowers. Also find it works with an automatic without needing to lock the TCC. Of course, higher rpm and lower gear will give intensify the exhaust brake effect if you need to slow rapidly, but alot of times for me the EBPV alone makes enough differnce that I dont have to downshift or ride the brakes on a long downgrade.