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failed smog because of fuel evap leak
#2
so, he did what,remove the gas cap.
then attached his leak down tool / engine off or running????
then saw with his tool or gauge, that your evap system will not hold pressure, that fails. (evap means gas tank venting system)
1995 has no OBD2 so no DTCs for evap here..
this forces them to do the crude tank leak down. cap OFF , (where was cap,? during test)??????????
and is hard to pass.
to find this cause, there are 2 ways, using pressure or VACUUM.

SINCE HE REMOVED THE gas cap and is not set aside, (was it)????

then the cap is not tested. and is top fail here. if he did use your cap, replace it now.... some refuse to test caps by them selves..
wish i knew his steps, and exact point of failure?
your photos are clear but no arrows pointing to your topic.

lets review how 95 works, it's real simple before 1996.

first off, not running engine the evap vsv is closed, and the vsv can not suck the evap tank. (canister activated carbon)
running and moving , VSV is open the vsv sucking the tank
but not parked.
but your smog man can not test this engine side, (not unil 1996) see?
the tank is tested only. at the smog station, and not past the check valve, pressure valve, near tank..(well unless iTS bad, stuck open)


this reg valve is closed. until a large pressure, builds in side tank(cold to hotday), say 1 to2 psi. and then the valve opens and pushes fumes in to canister.
it then collects them. this is why gas caps go whoshhhhh when unscrewed on a hot day. pressure there is normal
the vsv is closed, then when moving fast, the ecu opens the vsv and sucks and burns those collected fumes.
he cant test that ever. in 1995. cant.

if they use vacuum and it fails,(i dont know what he used)
the pressure valve near tank is closed. (as must be)
if the vacuum leak down test fails, its a bad leaking tank or a hose, for sure.
if he used say 1/2 psi ,as some do, so can you, and in most shops they use nitrogen gas at 1/2 psi.
then spray everything, there, near tank. all hoses and fittings.. there...
bingo bubbles, its soap spray like finding natural gas leaks, same spray ,home made

finger?
cant see it?

ask him did you pressure test my system or vacuum test it???????????
if no leaks found (soapy water +pressure)
then block the hose at the forward side of the reg.valve on main evap line near tank.
if the stops the leak, the valve is bad, its passive spring loaded valve , no elecrics there)

finding evap leaks can be easy look for damaged hose, or rusty tank top.

why is your egr hoses all wrong?
that rear, plenum fitting vac, is for 3sp a/t transmission, vacuum modulator , not egr
that will cause egr to be under hard vacuum all time time, very bad... with cat present.
or is that optical illussion for 2d photos. that egr mod valve looks like it going to that brown hard vacuum port.

i may be wrong, no fill flash and too many dark shadows.
http://www.fixkick.com
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Messages In This Thread
failed smog because of fuel evap leak - by vidas - 01-11-2016, 04:13 AM
RE: failed smog because of fuel evap leak - by fixkick - 01-11-2016, 04:56 AM

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