The bedliner concealed the 2 screws. There are some service bulletins but not for a Pathfinder. I'm new to all of this internet stuff. Ok so nobody has a pgm tester so now what? When this code sets it is because the fuse is blown. I noticed when I removed the hoses on the vacuum cut solenoid switch, it was a little moist with fuel.
The cause of this fuse blowing is a bad fan motor. I suspect that as the vehicle gets older this plastic plug system will break. . Hi guys, I just want to thank you all for your guys input. The vacuum cut valve prevents the intake manifold vacuum from being applied to the fuel tank. 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. You don't need the scanner to tell you what the commanded and actual cam positions are, the computer will watch that for you and turn on the check engine light if there is a problem.
Good luck with the diagnosis, hope you can find it. The vacuum cut valve bypass valve responds to signals from the. Sorry if you think that I should not get so technical. It is in … the shape of a black trapezoid approx. That's the most successful way I catch those stealthy little demons. Drew I spent a month trying to narrow down the code.
You need a time base of about 1ms to see this. If I did choose to go high tech 2 channels, one measuring voltage and one current on a time base that would clearly show what I wanted to see. Study how the system works, determine the code setting conditions, determine what components effect the system and develop a diagnostic plan from there. I am going in tomorrow. 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. I then replaced the the valve cut bypass valve four hoses going to it with a used one from junkyard.
There seem to be all kind of suggestions online. The housing has 3 screws that attaches it to the engine. Funny thing about vacuum lines, they never break out in the open, always behind or under something. It could be something as simple as a clogged hose. I'm getting this error code from my Nissan Pathfinder 3. Now I know that P1491 is Vacuum Cut Valve Bypass Valve.
Edited September 29, 2014 by zpmada. Ok so nobody has a pgm tester so now what? Try to use the Nissan speaker adapters plugs so you don't need to cut wires and mess up the electric system, you ca … n get those from eBay or amazon. There is usually nothng wrong, It is away for the Service Dep. It opens only for on board diagnosis. Stop at the first shut-off click.
Are you sure that is the right code? It ended up being the actual valve itself. If it reads less, go to step 2. The Inspection Station gave me a notice stating it could be 1. I am not sure if I had this code before I removed the upper intake manifold, or if it came as a result of removing the upper intake manifold. Suggestions on what to do next? This is not referenced or recommended in any way by Nissan, but my experiences have proven me correct, at least on my own 2000 4x4 Crewcab. Watching the wave form and verifying that the signal cycles between 0 and 12 volts with a clean square wave and an inductive kick at turn off verifies everything in the electrical circuit is ok.
Does anyone have experience with this problem? If you're really intent on scoping an intermittent problem we three know will be hard to capture, at least even your odds a little. Turn the bulb assembly counter clockwise to remove. The vacuum cut valve bypass valve is a solenoid type valve and generally remains closed. Another shop says there is no reason to replace a fuel tank to replace the evap can. If you are really partial to the Nissan logo you will probably have to order another, since it doesn't come with the tail gate latch assembly. Am I getting the wool pulled over my eyes by the dealer? I have done diagnostics as per service manual on everything except the evap control system pressure sensor. Pintle movement looks just like the pintle 'hump' in a fuel injector waveform.
They sell a device to reset these for almost any model of car made. That has the complete, step by step, procedure for checking the system. If this is the only waveform you are monitoring you only have a 50% chance of finding the problem. In the meantime, remove the battery from the remote to stop 'falsing' the truck anti-theft unit and use the key to unlock the drivers door. I would suggest ordering a few extra just in case they break one usually does. Sometimes swapping 2 components is faster than hooking up all your test equipment and the accuracy is always 100%.