where vacumn source is for the stock boost gauge and what are is the voltage range

[Bigguy0482]

All,

Two qestions..

1. Where is the vacumn source for the stock boost gauge?

2. What is the voltage range the stock narrowband o2 sensor runs at...

i.e what is the stoichmetric range at cruise and stickover and what is the ideal voltage at full throttle?

Thx

[volvotuning]

All,

Two qestions..

1. Where is the vacumn source for the stock boost gauge?

2. What is the voltage range the stock narrowband o2 sensor runs at...

i.e what is the stoichmetric range at cruise and stickover and what is the ideal voltage at full throttle?

Thx

1. Same as the pressure source. Inlet manifold.

2. Normally switches between 0.2V and 0.8V. It's completely non linear though. Come to think of it, it's not linear on wideband either but it's a much simpler curve to interpolate from. You will struggle to get a stoich reading of lambda 1.0 with a narrowband sensor. That's why the ECU uses the average values of the voltage swings to work it out.

Solution is simple - get a wideband!

Adam.

[Bigguy0482]

1. Same as the pressure source. Inlet manifold.

2. Normally switches between 0.2V and 0.8V. It's not linear though. Come to think of it, it's not linear on wideband either! You will struggle to get a stoich reading of lambda 1.0 with a narrowband sensor. That's why the ECU uses the average values of the voltage swings to work it out.

Solution is simple - get a wideband!

Adam.

Thanks adam,

My voltage seems to cycle between 0.8v to 1.0v (cruise/idle) do you think i have a dodgy lambda probe??

at rich it seems to peg to 1.0 v

[volvotuning]

Thanks adam,

My voltage seems to cycle between 0.8v to 1.0v (cruise/idle) do you think i have a dodgy lambda probe??

at rich it seems to peg to 1.0 v

Don't know. Is the fueling ok at idle and at cruise?

Adam.

[Bigguy0482]

it just seems to cycle at those values .8 to 1.0 volt.... i have a decat though... and one of your ecu upgrades...

[Bigguy0482]

just seems to cycle between .8 to 1.0 volt at idle and the same at cruise.... it has a decat on with some of your decat software on it...

[volvotuning]

it just seems to cycle at those values .8 to 1.0 volt.... i have a decat though... and one of your ecu upgrades...

like I said, get a wideband and you will know exactly what it's doing.

Adam.

[BlackBeast]

Im sure you can get widebands with a gauge for around £200 if you look hard enough, hope that helps.

[Bigguy0482]

like I said, get a wideband and you will know exactly what it's doing.

Adam.

Im wondering where it could be fuel pressure, adam in your rica upgrades do you change the fuel pressure?

[volvotuning]

Im wondering where it could be fuel pressure, adam in your rica upgrades do you change the fuel pressure?

No. Fuel pressure is not changed on the 850 T5. I don't understand what you are trying to do? If you want to know how it's fueling, ie AFR, then get a wideband. If you want to know the fuel pressure, get a fuel pressure gauge.

Adam.