Wat do i do 2 make da check engine light on a 98 chevy s10 come off so it can pass smog?

If the code is p0325, it should be repaired, HOWEVER, on nissan products from 1996 to 2002, a p0325 does NOT illuminate the check-engine lamp. Knock sensor on that vehicle is for PING control not for emissions reduction. On other vehicles (say a chevy with a p0325) it WILL light the check engine lamp which is an automatic smog fail.

DIYer? I recommend a repair manual from your auto parts store. It should provide a complete list of all error codes and likely repair methods. Otherwise find a competent repair shop, or your dealer. I googled your error code This is just one of the answers: http://repairpal.com/check-engine-light-with-code-p1870-057
I am sure you can do a better search since you know far more about the issues.

There are couple of things that has to do with emissions ,1 gas cap 2. Catalytic converter. 3. You have o2sensors better know as oxygen sensors unless u get a check engine light on dash you should be good just make sure car is warmed up enough so that when you go all sensors are opened on car for better reading .good luck

Take it to a different place to get it inspected, if there are no codes it should pass this test

Try to reset ,how long be off then go for test.

First thing you need to get the trouble code out of the computer.

check the timing

Go to your local shucks or auto zone and they can check any codes behind your check engine light and it's free. It sounds like one of two things a O2 sensor or your mass airflow sensor but they will tell you for sure

check main fuse's under the hood and yes that will trip checkeng light

get it repaired...duh