Starting in the last two weeks my engine has begun idling at 2000 rpm. Any idea what could be causing this? It does this cold or hot, and will slowly die down after idling for about a minute or so, but even then it only goes down to about 1500 RPM....

 

try lookin at the IAC valve, it may be gunked up and stuck open. Good Luck

 

What is the IAC valve and where is it. Thanks, also could this be related to my other post about the vacuum cannister being broken. I tried to connect a short piece of hose to the two male inlets that I thought the vacuum cannister could have been connected to, bypassing it basically, but it is still idling around 2000 rpm....

 

The IAC valve is the Idle Air Control Valve, it controls the amount of air goin past the throttle plates when they are closed to allow efficient and comfortable idle. Check the throttle body, it should be mounted to it with a few wires goin to it. You could probably just unbolt the little piece of intake just before the throttle plates, the piece that splits it in two, and just clean the whole area inside (throttle plates and IAC itself) wit carb cleaner. Good Luck

 

Thanks, I'll try that. I just replaced all the plugs, cap and rotor with no luck so far. It kind of annoying pulling up to a stoplight with the engine racing at 2000 rpm......

 

Before you start fiddling with the valves in your car, first it is a MUST to get a hold of the factory service manual for your car and give the read to a section 'EC', Trouble diagnoses. Your problem sounds like a serious vacuum leak. Mayhap it's time to buy about 9 feet of vacuum hose and replace all of them that you can find under the hood.

Once you are finished with repairing the cracked and hardened vacuum hoses, turn your ECU test mode screw all the way clockwise to close the idle valve completely. Then use the IACV screw to set the idle RPMs to 700 and turn the ECU screw all the way counter-clockwise. The computer may be left in any of 5 test modes, so do not get scared if the CE light goes on when you take her for a test drive. To prevent driving in test mode, first turn ignition off then restart the engine.

You may also have problems with the larger vacuum hoses - the PCV valve one and brake booster one. Those need to be replaced with the good ones from a junk yard or the dealer, depending on your budget. Check the PCV valve too, and of course make sure your plugs, wires, cap and rotor are Okay. Clean the white stuff from the contacts inside the distributor cap with a flat tip screwdriver or knife. The cap and rotor part applies to VG of course.

 

Its not the canister. IACV and/or TB as suggested; clean. FSM tells nissan "instant engineers" not to touch it. lol, that is right! But for any nonengineer who knows srew from nut, cleaning it is piece of cake.

Check for VGE details at:
http://www.cardomain.com/memberpage/748507/4

As for manual, go bottom of page one.
http://www.cardomain.com/memberpage/748507/1




Note: This was on page 9; test the stepper motor if suspect.