I have the efini turbos still sequential and the pfc. My boost gauge reads 9-10lbs and the pfc reads no more than .56. I raised the boost in my pfc from .74 up to 1.15 and the base duty any where from 30% up to 90% and saw absolutly no change in boost. What could be causing this?

 

Weird. .56 is about the wastegate spring pressure, which is 7psi. Either your boost gauge is really optimistic or something else is weird.

If you don't have the pills for the turbo lines, you'll always get 7psi, no matter what. Verify that you have the pills. And check for boost leaks as well.

Dale

 

I just checked and I do still have the pills

 

What else have you done to the car in terms of boost control? Is this a sudden problem, always had it? You have to give more info.

 

Its always read around 10psi on my boost gauge and around .50-.60 on the pfc.. a few months ago i got a greddy elbow and relocated the bov onto the elbow and welded up the stock bov holes. That is all i have in terms of boost controll is the pfc. For a while before relocating my bov to the elbow my boost gauge read 12-13 psi and pfc read .60-.64

 

Her altitude is around 5000ft so the reading on the PFC won't be the same as the boost gauge.....

 

ahhh..this was really bugging me earlier. Which one is correct then if the boost gauge is plumbed from the UIM?

 

Yeah why are the readings different? Ill WOT the car to check the boost pattern, PFC reads a max of .74 yet my boost gauge will easily hit 13psi, WTF?

 

raptor t, what boost gauge do you have? I have an autometer and it's +/- 1psi off from from what the PFC reads.

 

any ideas?

 

Since the PFC reads off the MAP sensor, I'd buy a 'tee' fitting, insert it into the MAP line, and read the boost gauge from there. If the numbers are still different, it's a calibration or altitude issue.

Dave

 

But why wouldnt the numbers change on both my boost gauge AND pfc when i raise my boost on the pfc? Thats what i most concerned about is why the pfc doesnt change anything when i move the settings anywhere up to 1.15 @ 90% i should see some sort of a difference but there is none.

 

depends on how you look at it. the map sensor measures absolute while the boost gauge measures relative. If you see 10psi on the boost gauge while 8psi on the map sensor, basically it means that you're still pumping 10psi via the turbo into the engine but the map sensor reads 8psi because of the altitude change. To verify this, you can turn the engine off and just read what the PFC tells you. The difference between the (negative value and the boost read from the PFC minus the inherent offset error of 1-1.5psi) should equal to the boost level you see on the boost gauge. I would expect her to see at least 12-13psi on the gauge while seeing only 8-9psi on the PFC.

 

could it be a solenoid causing the lack of response to change in boost settings in the pfc?