My local snap-on guy loaned me his scan tool, and i was looking through some stuff on my truck.

With the key on engine off, it was showing 16 PSI of boost, and reading about 30 PSI of boost at WOT ( which is what my gauge is showing )

Is that normal ? Is that where i'm loosing so much of my fuel mileage ?

i also noticed that my IAT sensor does increase much in temps when under full boost, not much more than 10-15*f

workin on testing it with a dodge scan tool tommrow from another local shop !

 

Youre showing boost at idle?? Um no. You cannot have boost with just the key in the ignition - also theres no boost with the truck at idle either. What kind of guages do you have? Is that an electric boost guage?




Wish my truck did that...

 

what kind of gauges do u have

 

hey change your boost aka your map sensor it will go back to zero been there and did that

 

You have to remember that many scanners are reading true pressure. This means at sea level, you should read over 14psi.

Now if you want boost above that, you have to subtract ambient air pressure.

Dave

 

Like Dave said it is reading Barometric pressure. So it will go up from there. It doesnt actually have "boost" at idle. No worries

 

but he is testing the new whipple turbo

 

so if 14psi is with no real boost than my stock head gasket has successfully held back 74PSI of pressure ... Sweeet !!!

 

Ummm, no.

Gauges are calibrated to be zero at ambient atmospheric. This is why 1 psi is 1 psi, not 15+.

Dave

 

Yeah, its known as PSIG, Or PSI gauge.