Getting knock sensor (0304) code from ECU on a friend's '96 Max. Cleared 0304 code and it comes back again after a short drive. Went to test the sensor at the harness for continuity. Which leads do I test? The ones inside the small gray male connector or the larger ones inside the larger black female connector? They of course give different results and I can't tell which connector leads to the ECU adn which one leads to the KS. Also, do I really need a 10M-ohm meter or can accurate results be obtained with a regular 2M-ohm meter? I don't want to replace the KS unless I know it is really bad and not just throwing off codes due to pinging as he does sometimes run 89 octane gas (we did however put premium in before clearing the ecu and getting the 0304 back afterwards). Thanks

 

I've be getting the same code (0304)....Does your friend's car have a clicking sound in the engine bay while idling or when the key is set to "on" but the engine is not running? Sometimes the same code 0304 will also be triggered if the IAC valve (idle air control) is faulty. You may also want to check it.

-M

 

You can use a 2 ohm multimeter, because the resistance is about 550k ohms, so its fine. There are 2 harnesses you can test, one that is on teh KS itself, and another one in an easier place to get to. If you follow the wire that comes from the KS, it leads to a sub-harness. You're going to put the red on the pin that leads to teh KS, the other pin is the ground. The black wire on the DMM you can just put on the battery ground. Remember teh KS needs to be grounded when you test to get the correct results. 550k ohms is a good KS.