Engine light stays on with the code p1706 what does this mean? I have a 1999 nissan altima gxe.

There is a strange procedure for this!

https://www.palmspringsnissan.com/blog/how-to-completely-turn-off-the-headlights-on-my-nissan/

https://www.google.com/search?q=1997+Nissan+Altima+GXE.+The+Daytime+Running+Lights+won%60t+turn+off

..

find out what's the trouble code:
http://forums.nicoclub.com/how-to-read-obd1-trouble-codes-for-1993-1995-j-s-t217489.html
then post back

• cod 1491

the whole service engine light soon is on for just about everthing did you check to see if your oxegen sensor was good when you do an oil change you can reset the miles that you went and when you reset it you see how much miles you get from the new oil

www.engine-light-help.com/generic-check-engine-light-codes.html

google nissan altima resistance info you should be able to get more info than youll ever need.

Crankshaft and camshaft position sensors possible

try looking at the coil thats what they do work then suddenly stop working

Code P1491 is not the PVC Valve.It is the Vacuum Cut Valve Bypass Valve.
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. if it is from a check engine light that says look at vacume cut valve check the egr canisters purge valve some times they stick and throw the wrong code

I switched one of the new bulbs with a working older bulb, and the problem went away. weird...