illios

what sensor is this above the map sensor? on the gsr mani? my minifold is missing this... do i need it?

93egSLEEPER

looks like an evap sensor/system possibly, hard to tell completely from the pic included. does small rubber hose attach to the nipple on it?

illios

probably lol i dunno. its not my pic lol. im just seeing if i need it cuz my mani is missing that

raidacaipo

evap purge solenoid I believe.. for usdm ecu's and emission purposes.

D16SiHatch

if using an obd1 ecu, you don't need it. if obd2, then you do.

raidacaipo

Only if its a USDM obd2 ecu.. JDM units dont look for these sensors..

deadazleep

that is defiantly the evap purge solenoid. I used a junkyard SOHC to put on my b16 cause mine was broke. Didn't notice a difference with or without lol

D16SiHatch

true. seems like the majority of people use usdm ecu's though

illios

oh i see, ima probably be using obd1 gsr ecu, so i should be fine without it correct?

raidacaipo

yes

Vindicator9000

correct.

also correct.

Basically, there's a valve in the fuel tank that releases fuel vapors into the charcoal canister. When the pressure gets high enough, it opens the evap purge valve and allows the fuel vapor to flow from the charcoal canister into the intake manifold to burn. The catalytic converter then cleans the exhaust, thus reducing emissions.

It's for emissions purposes because it's generally considered bad for the environment to vent fuel vapors into the air.

On a USDM OBD2 ECU, it will usually throw a P1456 or P1457 code if it's missing or functioning incorrectly. You may also notice an increased risk of overflowing the tank on fillups.