AP Boost and Gauge Boost

[Dano2010]

probably because you are trying to keep the wheel straight from all the torque steer and wheel spin ;-)

but serously if you are -22 at idle you shouldn't have any leaks. If your AP is showing 2 PSI more than the guage, it's just the guage's sending unit that is off more than likely [my Prosport shows 1.5 PSI more than my AP but only sometimes..whatever] If you had any hose leaks the AP would be showing less boost than expected as well.

 

[SallySpeed3]

Well, last night i disconnected my battery because I read somewhere that the electronic boost gauges remember what your "max" boost is. So I figured since i added the AP, my boost is now different, so I thought disconnecting the battery would maybe do something. In doing so I noticed the wire that powers my sending unit wasn't exactly secure on the fuse I tapped it to, so I'm thinking theres the problem, but who knows? I'll swing by radio shack and pick up some more connectors. But on a side note, will resetting your ECU screw up the cobb flash at all?

 

[Dano2010]

not at all, that flash is there until you change or remove it with the AP.

 

[SallySpeed3]

good to know thanks

 

[MSMS3]

Well, last night i disconnected my battery because I read somewhere that the electronic boost gauges remember what your "max" boost is. So I figured since i added the AP, my boost is now different, so I thought disconnecting the battery would maybe do something. In doing so I noticed the wire that powers my sending unit wasn't exactly secure on the fuse I tapped it to, so I'm thinking theres the problem, but who knows? I'll swing by radio shack and pick up some more connectors. But on a side note, will resetting your ECU screw up the cobb flash at all?

I just now realized that your boost gauge is not mechanical and relies on a separate sensor that converts pressure to electrical impulse. Maybe fixing the wiring will resolve the discrepancy in readings.

So what we've been discussing all along is a discrepancy between two electronic sensors sending signals that are electronically interpreted as pressure readings rather than taking a direct pressure reading by mechanical means. I hope the electrical signal from the sender was weak due to the wiring problem and this resolves the difference. If not, the sender may be defective.

I'd still want to know if a true mechanical gauge connected directly to a vacuum line agreed with the AP. That would be a good way to resolve any continuing discrepancy with the Prosport gauge. If you not have one, just about any good independent auto repair facility should be able to temporarily connect a mechanical gauge and resolve the issue, and do so very cheaply, or for less than $50 you could get a very reliable OEM supplier mechanical gauge from the manufacturer that outfits most upscale European turbo cars - VDO, even if it is never mounted and used just for diagnostic reference. Just a thought . . .