Questions about the altitude sensor.

[k.alle]

I've read some old threads about this unit, but no conclusions on how to actually determine if it's knackered or not.

Are there any updates on this one?

I've measured mine:

Resistance
Pin 1 -> 2: 1327 Ohms
Pin 2 -> 3: 2417 Ohms
Pin 1 -> 3: 2765 Ohms

Voltage
Pin 1 -> 3: 3.942 Volts


Atmospheric pressure: ~1.000 hPa/mBar
Temperature: +23-24°C
Im about sea level.

So how should I take these readings?



The reason I'm asking is that I sometimes only get 1.2Bar boost when I should have 1.4Bar and if I release the throttle and push it again I get 1.4 bar.
And I don't have the torque I should have, according to my butt dyno.
The horsepowers is there but not the torque, you know when the whole car almost squeels in agony when the torque hits in and you find yourself almost sitting in the boot

Cheers

[Rusty]

Sonds like the lottery that is overboost to me...

[k.alle]

Oh, is it a known problem, it not functioning properly?

I wonder why I'm missing out on the torque side, even when I'm on 1.4bar of boost.

[Rusty]

Sorry, I was referring to the different boost that you were getting. If you're not aggressive enough on the throttle or low enough in the revs then the overboost does not come in. What chips are you running?

There are a couple of threads with the altitude sensor values in.

Plug VAG com in and see if it thinks you're on the moon or something

[k.alle]

I was just out, and sure enough when I was violent the boost came to 1.4Bar, just never thought about before.

I run with PowerChip's chip (lol), a company here in Sweden.
The chip should give me 280HP and ~450NM.

LOL, on the moon
Got to get my VAG-COM cable working...

[Rusty]

Sounds like overboost to me then, that's the same as the standard chips. Real pain, ****y marketing gimmick.

[k.alle]

How do you mean?

That it has not 280 HP, it's still original?

[Rusty]

No, the chips obviously still have the overboost turned on, a lot of tuners get rid of it now but that's not always been the case. 1.4 bar certainly isn't standard

[Mark Halligan]

No, the chips obviously still have the overboost turned on, a lot of tuners get rid of it now but that's not always been the case. 1.4 bar certainly isn't standard

The important thing to check is the voltage output from the sensor across pin 1 (+) and pin 3 (-), it should be around 4.1 volts at sea level'ish.

Full explanation here http://www.sjmautotechnik.com/troubl...ng/20valt.html

[k.alle]

No, the chips obviously still have the overboost turned on, a lot of tuners get rid of it now but that's not always been the case. 1.4 bar certainly isn't standard

Oh, now I get it, sorry about that

The important thing to check is the voltage output from the sensor across pin 1 (+) and pin 3 (-), it should be around 4.1 volts at sea level'ish.

Full explanation here http://www.sjmautotechnik.com/troubl...ng/20valt.html

Hmm, so my 3.942V @ 50-100m (pretty much sealevel) is too much off?
What problems do this unit cause when it's not accurate?
Don't want to buy a new one just to find out.

[k.alle]

Anyone knows if I should be worried with the altitude sensor giving a 3.94V output @ sea level.
How critical is this?

[Val]

What's happening if altitute sensor is NOT connected?
engine: a4 b5 1.8T aeb