I have newbie question. Under normal driving conditions, what should EBP readings be? Should they fluctuate? My reason for asking is I recently installed an Edge Monitor and have noticed sometimes my readings will increase but not go back down. Is this an indication that the valve is sticking? And does it effect fuel mileage? Because my fuel mileage sucks!

 

My EBP is usually about 14 PSI at idle and 17 PST running. Since I have a Interceptor Scan Gauge and it does not subtract Barro I just see Back pressure plus atmospheric pressure. When I had a working EBPV and it was a cold morning, < 32 F then the back pressure could go over 40 PSI as the valve was closing attempting to heat the truck up faster. Of course your injectors are different then mine, I have stock.

What kind of numbers are you seeing and under what type of driving conditions, that would help understand your particular situation?

 

I'd say if it is not fluctuating evenly with the boost then the EBPV may be restricting it from coming down. Below is a sample from the Torquepro app that shows the EBP pretty close to barometric pressure (14.7ish) plus boost. I do not have an EBPV, and just fixed my leaky EBPS tube this summer with a new sensor.

 

I'm not getting anywhere near the readings that y'all are quoting. I think the highest I've seen on mine is 8psi.

 

^^^^ That's relative to atmospheric. The numbers above are absolute.

 

Are those numbers from your truck?

 

The numbers on mine never seem to coincide with boost pressure. I'm not really sure how this works. But, like I said, mine never gets above 8.

 

Bottom line is that anything restricting exhaust flow through the turbine of the turbo is going to cause a decrease in fuel mileage. This is the same for leaky up-pipes or a leak in the turbo outlet into the plenums.

If your EBPV is malfunctioning and obstructing the exhaust side of the turbo then your EBP will remain a constant high while boost is reduced. You need to look at what your back pressure is at idle. It should match barometric pressure within a couple of tenths.

The torque log above doesn't account for atmospheric pressure of roughly 14.5 psi, so the highest reading is actually 24.1 minus 14.5 for back pressure of 9.6 with boost at 11.8 psi.

 

My EBP and boost seem to stay about 15 apart..sounds normal?

 

Is EBP measured in absolute pressure, or relative to BARO?

 

absolute
10 char

 

Then 15 psi difference makes sense. Atmospheric pressure is 14.7 psi at sea level, so probably 14-ish where you are. So that puts EBP close to MAP, which I've read is a healthy sign.