blueg6

well thats fine, i have a friend with one he said we could trade if i needed it.

ekb16

iTrader: (1)

i forget its not obd2 so they will prob not use a scanner on it but its still a good idea to run a USDM p72

blueg6

back to my original question.. could having the nissan gas cap on my car make me fail the evap test? im gonna switch the hoses incase there is a leak.

honda.lioness

Underneath the fuel filter you can see the top of the charcoal canister. It has three hoses connected at the top. The hose labeled #7 should go to the purge solenoid valve or a similar control valve that, upon engine warmup, admits vacuum to hose #7 and so the top of the diaphragm on top of the charcoal canister.

Was just testing all the canister's lines on my 91 Civic using the shop manual.

ekb16

iTrader: (1)

i would switch the cap just in case bcuz the ref. will take off the fuel cap and cap it onto the machine to test it

blueg6

so what your saying is i have it?

honda.lioness

I am saying you should see where hose #7 goes. It connects the top of the diaphragm on the top of the charcoal canister to... ?

The hose attaching to the top of the canister and nearest the firewall is supposed to go to the fuel tank via the two-way valve. The red, larger diameter hose beneath hose #7 is supposed to go to the throttle body. At least, this is the setup on stock systems.

But from my reading, for this CA BAR test, the hose nearest the firewall is pinched off and the fuel tank is pressurized yada. Get the OEM fuel cap, like the other poster said, first.

blueg6

both of the hoses are labeled 7 but whatever. one of the hoses runs from the bottom of the solenoid to the backside kinda of intake mani. the other hose runs from the top of the solenoid to the charcoal canister

thesmogman

The gas cap is a whole different test. So no it is not the gas cap.

The Evap test or LPFET for low pressure fueltank evap test is what you failed for.

Here is the low down. All the test does is check for vapor leaks.

We pinch off the vapor line just before the carbon cannister and the have adapters to seal off the tank (where the gas cap goes) Then we have a little test system that puts a 1/2 a pound of air into the tank(Through the adapter). The system then measures for a leak. Any leak, down to a pin hole it will measure and fail you.

Now this leak can be either...
1. the vapor line itself. Which runs inside the car. On the carbon cannister, the hose is the one by itself closest to the firewall. The hose goes to a metal line on/through the firewall.
2. the gas tank seal (where the fuel pump goes) Might not be tight enough
3. the filler neck hose or vent tube.

So there you have it! This is what failed you.

blueg6

so i found the problem guys. some jack *** who had the car before me drilled a hole from the inside into my gas tank. i dropped the tank and plugged it up with some jb weld. gonna get it tested in the morning after school. thanks guys!

blueg6

one other thing. so my intake manifold is fine correct? it is the JDM manifold but everything is hooked up like it should? correct me if im wrong please.

honda.lioness

The #7 hoses look right. You can do a quick check on them: When the car is warmed up (drive 15 mins or so and fan comes on once), disconnect the #7 hose from the canister top. Do you feel it pulling a vacuum? If so, then it is probably fine.

blueg6

if it all looks right then i know its working. i just had all this done by my friends' shop. i really appreciate the help.