F96 Altitude sensor problems

[twoqu]

If you try and read them using a range of less than 2k you will get the reading of 1 on your multimeter for those greater than 2K.

[gmac78]

twoqu- you got me thinking there so went out to the garage to have a closer look at my multimeter. The range stampings are faded and i actually had it on 2k rather than the next step up 20k. I'll recheck the resistances in the morn to see how i get on. cheers dude.

[UrS4boy]

What the Bentley Manual says about the F96 is: with the three pin connector disconnected and with the wire bale up and the notch in the connector down, the three female connector pins are, left to right, 1, 2 and 3. With the ignition on, you should get 4.5 to 5.5 volts between pins 1 and 3 and pins 2 and 3, if not, there is a voltage issue related to the ECU. The only mention of ohms is 1 ohm maximum.

[BorisShakhov]

I thought that we can see atm.pressure in VAG-COMWhy you don`t just check there?

[twoqu]

I thought that we can see atm.pressure in VAG-COMWhy you don`t just check there?

That measuring block is not available on the 3B!

[gmac78]

Afternoon all,
Tested voltages and resistances again today but this time using the correct range on the multimeter!! It turns out it was set at 2k ohms yesterday which was giving me dodgy readings. With ignition on today at sea level i was getting-
1-2 0.96v 1.1k ohms
1-3 3.97v 2.57 k ohms
2-3 4.95v 2.43 k ohms

Do these readings look normal to those in the know?

Also, i decided to disconnect the F96 and take it for a spin to see what it would boost to. I fully expected disconnecting it to throw a fault but it never.
Is this right???

When driving it made no difference to boost being connected or disconnected. Still not getting overboost, managed 1.3 bar max.

Any ideas why it's not throwing a fault code or reducing boost when disconnected?

Cheers guys

[UrS4boy]

F96 Altitude/Barometric Pressure Sensor Information

This might help you figure things out.

http://forums.quattroworld.com/s4s6/msgs/21892.phtml

[Rusty]

What intercooler do you have? Homefries still has the inlet air temperature compensation map on the ABY, not sure if this applies to the 3B?

[gmac78]

Not sure if the inlet air temperature compensation applies to 3B or not? I am still running the standard 3B intercooler. I have recently replaced the MAf with a reconditioned one from ECP. The old maf was giving me rough off boost performance but when on boost would achieve 1.4bar. The new maf has solved all the rough running issues i had but now never really see the full 1.4 bar like i did previously

Not sure if the maf would cause this or not?

I checked the IAT this morning and was getting a reading of 480 ohms, it was still early and not that warm outside maybe 10 degrees or so. Does this reading seem normal for the temperature?

Does anyone know why disconnecting the F96 didn't throw a fault code?

Cheers

[martinws]

I've been having a similar problem with my ABYed 90. In 5th at low speed(full load) it boosts round to 21-23psi (prj ecu) but only around 16-18psi in other gears. I've tested pipe work between MAF and throttle body to 22psi no bother.Can I pressurise the inlet manifold easily to check all vacuum lines as well?