Is there something wrong with my AP? My Boost Pressure column shows negative numbers....I'm running AccessPort Firmware 1.6.0.0 - 13766. I thought this was fixed a few firmware's ago??

Baro. Pressure (PSI)
14.36
14.36
14.36
14.36
14.36
14.36
14.36
14.36
14.36

Abs. Pressure (PSI)
20.09
16.61
5.44
19.72
20.09
9.14
2.76
7.25
10.15

Boost Pressure (PSI)
5.73
2.25
-8.92
5.37
5.73
-5.22
-11.6
-7.11
-4.21

 

Are these values with a load on the engine? If not, the AP is reporting vacuum which is fine.

 

Boost Pressure = Absolute Pressure - Barometric Pressure

 

I'm trying to figure out why some people who are logging have a Boost PSI that is correct...are they just taking the absolute pressure - baro pressure and making a new column before they post their logs?

 

Vacuum is negative boost. We can't boost all the time.

 

There is nothing wrong with the data you posted. You aren't understanding what you read. There are about 2 inches mercury of vacuum for every "negative" psi. so if you are reading -7 psi that's like seeing 14 inches of vacuum on your typical autometer boost gauge.

 

I understand what the end result is - how are others getting the data from the data log w/o modifying the columns? It doesn't post into virtual dyno unless i manually go in.

And my overboost issue has gone away since i moved to stage 2 lwg - never caught it via log on regular stage 2 but asc kept turning off when i gunned it (yes fluid is full and never had issue prior to tune and then instant asc off multiple times when at high accel

 

lol

 

Ok...just ran a few more times...can someone please explain these logs to me? I'm not understanding why my boost doesn't build and hold - something must be going way over my head...

Thanks

 

also - should i put the boost pill back in even though i'm stage 2?

 

Damn so i set the map back to regular hks stg2 93 oct and threw the service light on the first pull in 3rd gear....pulled back in driveway and shut off car...forgot to hit the stop logging button and the AP saved the log as 0kb and unreadable. Ran again and it didnt throw the light but I hit 28.06 psi - should I reinstall the pill?

Vehicle Speed (mph) RPM (RPM) Boost Pressure (PSI)
8.7 1985 5.58
13.67 2629 10.08
13.67 3536 23.71
22.37 4693 26.69
22.37 6048 19.87
34.8 7088 -9.43
39.77 6112 18.06
39.77 5486 27.27
47.22 6062 24.29
47.22 6643 5.22
55.92 6874 8.34
55.92 5215 28.06
58.41 5584 27.41
64.62 5919 24.51
64.62 6286 20.59
70.84 6579 19.07
70.84 6855 7.32
77.05 6666 -11.17
75.81 5742 -10.8
75.81 5219 -10.37
65.87 5088 -10.59
65.87 4908 -10.59
53.44 4702 -10.8

 

It would help to know what mods are done to the car. You can always flash the LWG maps, 28 PSI, is slightly spiking. Has the WG arm been tightened?

 

yeh..

PSIG = PSIA - BARO

Most folk just get a rough reading for their Baro (ie 14.3) and subtract that instead of logging Baro...

 

No (Is there an issue?) - I'm going to flash back to the lwg map but that is still spiking to 27. I have the hks drop-in and a turbo xs tbe. I haven't seen any other logs like mine and I'm getting frustrated b/c I don't know what I'm reading and don't want to ruin anything. It's also getting colder out in NY so i'm not sure if that has anything to do w/ the spike issues.

Thanks for the help

 

i have the same issue you are. I have the full stage 3 perrin with a tune for everything, boost pill is in and im boosting at 29-29.5psi and the asc light comes on if i floor it so i just started shutting asc off so i stopped getting that error message but the boost is the same issue with me but im in stage three and its supposed to be at peak 28psi and i messed with a few things and dropped it .7psi