In the last couple of weeks my Jeep started making a light tapping sound then a couple of days ago my Check Engine light came on. I hooked up my scan tool and it coded P0520 (Engine Oil Pressure Sensor/Switch Circuit). I’m assuming it needs the sensor replaced. I took it to a local mechanic to have a diagnostic ran on it because Jeep could not get to it for 2 weeks. This is the diagnosis, “Check Engine Light Has Codes For Oil Pressure Sensor and Speed Control”. Then he said the mechanic said ”The Tapping Noise Is From Valvetrain In Bank One which he said is the driver’s side”. That was not a code but just the comments from the mechanic. He said to replace the speed control and the oil pressure sensor which they would do the cooler as well would be a little over $1100. He said I would have to go to the dealer to have the valvetrain checked because he does not do that detailed kind of work. I wonder if the mechanic just didn’t want to do it or if there really is a problem with the valvetrain Since it didn’t code. I looked into trading but geez the prices are really high. So I’ve decided to replace the oil pressure sensor myself to see if that fixes it and hold off buying one for a while. I called the dealer to price the sensor and the cooler and it’s $424. Is it necessary to replace the cooler as well like the mechanic stated? Because the sensor is only about $50. Would the oil pressure sensor cause it to be tapping? I have always took really good care of my Jeep and the dealer has always done the oil changes, brakes and other maintenance type work on it. I was going to get a second opinion on the diagnostic but Jeep wants $205 to do it. So I thought I would do the sensor first and then go from there.