It's possible that the valve wasn't really your problem, or that there is more than one problem. Pulled the metal cage off and plunger dropped out. Description: This post describes one of the diagnosis steps for the P1491 codes on a 1999 Nissan Altima. It is about halfway between the fuel filter and spare tire on a little ledge bolted to the wall. I don't want to drive it like this because it's dangerous yesterday when I released or opened the gas cap I heard a pop as if the tank had expanded and when I let the air out it popped back into place but not for sure that's what happened. You will find page for page lectures taken right from my book as well as exclusive classroom type case studies.
I decided to begin with the canister. If your charcoal has broken up, catching it early on may prevent the stuff from getting sucked into the system, clogging your hoses and solenoids. There is no better on-line training of how to troubleshoot automotive electrical and electronics systems anywhere! There is a 14 day free trial. Got this code while coming home from work. It seems like the plunger isn't sealing off internally when the coil is energized, even if pressed the plunger down by hand with good force it would not seal. P1490 Nissan Description The vacuum cut valve and vacuum cut valve bypass valve are installed in parallel on the purge line between the fuel tank and the canister.
Vacuum cut valve bypass valve solenoid above, vacuum cut valve below. Two of those hoses go to a solonid valve with a two wire electrical connection. The vacuum cut valve is then bypassed to apply intake manifold vacuum to the fuel tank. I hope this helps others. After that you replace this device, if the light goes out and stays off for 200-300 miles, then the vehicle will pass inspection. The line that was plugged solid with rust was a hose coming from bypass valve that split off to a hard line that was routed through wheel well looks like a brake line. Start by tighten the gas cap and clearing the code.
I would suggest a swivel socket to remove the bolts that hold the valve on. Two of those hoses go to a solonid valve with a two wire electrical connection. I looked this up and found it to be a. Two similar codes exist for this system: P1490 and P1491. Replaced the line with one I made and the trumpets started to blare in the sky with approval. .
Took apart valve cut bypass valve popped the top off with small slotted screw driver and cleaned inside which had debris in it,seemed to be rust or small granules inside. On my 2002, it is located against a rear wall, opposite the fuel filter. You can try to replace the valve but I cannot guarantee that this will solve your issue. Gasoline in the signal hoses from over filling the tank can cause the tank pressure sensor to send the wrong evap emission information to the Engine computer that in turn sets the P1441 code. Protip: search 'nissan cut valve' instead of listing your specific model, as this Nissan part is the same across many different models. So, I went ahead and replaced the valve.
The vacuum cut valve is then bypassed to apply intake manifold vacuum to the fuel tank. Material may not be copied or reprinted without written permission. Als check the next items: - Incorrect fuel tank vacuum relief valve. The vacuum cut valve prevents the intake manifold vacuum from being applied to the fuel tank. Eventually I traced the hoses upward to the vacuum cut valve bypass valve.
Even if the cap looks ok it may need to be replaced. Disconnect two 2 lines from the Vacuum Cut Valve. Good luck and keep us posted. The vacuum cut valve bypass valve is a solenoid type valve and generally remains closed. Te same problem we foudn in a Sentra 1. The vehicle must complete a drive cycle after the light goes off so that it will pass inspection. I had a 1491 error code drive me crazy.
Service Engine Soon light came on at around 65 miles, as usual. Gasoline in the signal hoses from over filling the tank can cause the tank pressure sensor to send the wrong evap emission information to the Engine computer that in turn sets the P1441 code. The purpose of the vacuum cut valve white part in the pictures below is to prevent the intake manifold vacuum from being applied to the fuel tank. If you have an older vehicle and a few spare hours, I recommend you do the same. When is the code detected? The vacuum cut valve is then bypassed to apply intake manifold vacuum to the fuel tank. This is an emission issue, and will not cause any issue with driveability. The vacuum cut valve bypass valve responds to signals from the.
Replaced electrical connector and all is good. It is the Vacuum Cut Valve Bypass Valve. This verifies the intake manifold vacuum. Didn't notice any performance change. I couldn't really see above the ledge, but I noticed two rubber hoses around it that were not connected to anything, so I figured that must be the problem. It had two broken hoses sticking out of it.
This is only the first time that I put gas on the truck ever since I bought it. Wound up snapping one of the bracket bolts. Which is located above and away from the egr canister under the driver side rear bumper it is round and have about 3 hoses connected to it. In most cases the code can be clear by disconnecting the car battery for about 30 minutes. My old valve looked about as corroded as yours. The vacuum cut valve prevents the intake manifold vacuum from being applied to the fuel tank.