Hello my name is Junior and I have a question on my 1999 Nissan Altima gxe. My car shakes while it idles, the rpms go up and down on its own, and in some cases it stalls while in neutral. Since the check engine light is on I took it to Auto Zone a few days ago for a diagnostics. I got a code that read: P1490 which means vacuum cut valve bypass valve (circuit)? I am really confused on what this means exactly. I have changed my spark plugs and looked for "vacuum leaks" by spraying carburator cleaner around the intake manifold with no luck. If you could please help me out on how to determine what it is and give me some tips on how to fix it, i would greatly appreciate it. Thank you for your time.
Jan 23, 2014 at 5:52 PM