Codes come and go!

[tico1965]

I have a 99 QX4 and I have a couple of codes that come online and then the don't. I will clear the eng light and after about a day then the light will come on. One is the Eng Knock sensor, this one does not go away so I believe that is correct and I will have to break down and fix it. Then I have a EVAP code that comes and goes, a high voltage that comes and goes and a sensor.
When I clear it the light goes out, a day goes by and the light comes on, it will show a Evap or a Sensor and sometimes the high voltage (generic).

Any one have this come up?

[Chuck Tribolet]

What are the specific codes?

An intermittent problem will come and go.



Chuck