Engine Code Evap has big leak

[trigun7469]

When ever I drive on the highway for over a hour a check engine light comes on says that I have a big evap leak, I clear the code and then I changed the Evap hoses, but it still comes on, what else should I be looking for? MPG don't seem to be effected by the problem, and street driving does not trigger it. Thanks

[lumpylarry]

likely the evap vent valve stuck open.

[jim_naisium]

What is the error that it is giving you?

[Isuzuzuki man]

Try a new gas cap.

[trigun7469]

Originally Posted by lumpylarry

likely the evap vent valve stuck open.

How would I be able to check that?

unfortunately I forgot to write down the code next time it happens all post it.

[lumpylarry]

remove the valve, depending on which model you have, it may be under near the tank or in the engine bay if thats where the canister is.

with the valve out of the car, air should flow freely between the 2 ports.
using jumper wires, apply 12v across the pins of the valve.(a 9v battery will also work)
you should hear a solid "click" and air should no longer pass through the valve.
if yours is the one near the tank, you will be able to see the plunger move inside the valve when voltage is applied.

you can also measure resistance, should be 25-30 ohms

if there is no click and air can still pass through when voltage is applied, replace the valve.

hope this helps

[trigun7469]

Originally Posted by lumpylarry

remove the valve, depending on which model you have, it may be under near the tank or in the engine bay if thats where the canister is.

with the valve out of the car, air should flow freely between the 2 ports.
using jumper wires, apply 12v across the pins of the valve.(a 9v battery will also work)
you should hear a solid "click" and air should no longer pass through the valve.
if yours is the one near the tank, you will be able to see the plunger move inside the valve when voltage is applied.

you can also measure resistance, should be 25-30 ohms

if there is no click and air can still pass through when voltage is applied, replace the valve.

hope this helps

Is that off of a 2001?

The engine code is P0455

[lumpylarry]

1.8 or 1.6?

[trigun7469]

Originally Posted by lumpylarry

1.8 or 1.6?

it's the 1.8

[lumpylarry]

yup, thats the one. its located right behind the fuel tank on the cross member.