PCV NOT READING MAP VOLTAGES.

[turbokz]

I just got my power commander 5 wired up, and its reading rpm accurately, and I have my analog map input setup correctly (something like 1.5v = 0psi, 4.5v = 32psi). While the bike is running, it stays in the 0psi range and leans out (obviously b/c not referencing map). My question is, does the pcv read reverse voltage? Anyone on here have success with the pcv??

[Lorcan]

Mang? I've only used a PC3.

[Mang]

Indoors at the moment and looking back on the notes my pressure to voltage conversion readings are about the same as yours . Without re reading the PCV manual for confirmation I don't think the voltages are reversed so i am not sure what the problem is. If I remember correctly the TPS voltage is reversed.

let me have a look later and I will work out what I did. Its that long since I set it up i can't remember the detail.

[dazbo]

i would imagine that the sensor will not give a reversed voltage but will give a lower voltage at vacuum. what you need is either a negative pressure column or your lowest bin value should be at your idle voltage.
i.e make your scale something like 1v(or your actual reading at idle) -4.5v
i hope that makes sense.

[Würstchens-Turbo 810]

Sorry for this question .
I use a PV3usb and i thought it works to 5V ?? (or am i wrong with this ) ?
The PCV is 4,5 V ?
I use a second boostsensor 0 to 5V

[Mang]

PCV is 0-5V

[Mang]

Indoors at the moment and looking back on the notes my pressure to voltage conversion readings are about the same as yours . Without re reading the PCV manual for confirmation I don't think the voltages are reversed so i am not sure what the problem is. If I remember correctly the TPS voltage is reversed.

let me have a look later and I will work out what I did. Its that long since I set it up i can't remember the detail.

Just has a good look back at this and did a quick test by putting a positive pressure on the bike sensor (yes it is 5am Christmas Day but everyone is in bed)- I can tap into the pressure sensor line very quickly - I made it this way for in situ calibration purposes. i can confirm the voltage is positive and rises with increased pressure.

The PCV3 instructions in the "how to" section explain how to establish voltages for different pressures. They advocate using a tyre, I made something a little more sophisticated using a pressure restriction valve and a gauge all connected to my air compressor.

So what would I check -
pump up the sensor in situ and check the voltage is being generated from the sensor to the PCV
check its not going over voltage, remember the bike generates 0-6V and the Power Commanders max out at 5V. They do say this is not a problem if you go over voltage but I have never had the desire to try it.

Other than the above I am at a loos to offer further help as to why it is leaning out.

I only had real success with PCV when I used the Electrical Noise filters from Dynojet. I know other members have used them with good results and they are easy to install in the PCV. Our bikes generate a lot of noise and it can throw the PCV

Hope this helps

[Mang]

viewtopic.php?f=13&t=17640

thread on noise filters