2000 ram van 1500, 3.9 v6 with 116,000 miles. I got a check engine light that sometimes comes on and sometimes won’t, scanner says cylinder 4 misfire code but I have no performance issues (no shaking, noise, loss of power) and my gas mileage is better than ever. Could this be a sensor malfunction? What should I test for?

 

Not sure how the PCM determines misfire. I suspect it has to do with crank sensor..... But, if the van runs good, the sensor is doing it's job. Think I might be tempted to inspect the plugs/wires/cap/rotor, and see what ya got.

 

It could simply be a bad spark plug or plug wire.

 

Yep - I agree with plug wire. The only ones I can use that don't give me misfire codes are the really good ones. I find the cheap ones are only good for 10K miles or so...

Also there is a TSB for spark plug wire routing. Today, I just cover all of the wire I can with conduit. It seems to help.