Nissan 370Z Forum - View Single Post - High-Pitch noise in the car

ZKindaGuy · 09-06-2009, 11:34 AM

My 370Z started to have the engine bay high-pitch sound. I traced it to the area of the ECU (or ECM = same damn thing). It reminds me of a high-voltage sound that is typical of electonic circuit boards that have developed a cold solder joint (crack). Once the board heats up enough to expand the solder the joint/crack gets temporarily bridged by the solder which then will cause a voltage disparity which produces such a high-pitch noise. Once the board cools off sufficiently to contract the solder the joint/crack sides move back into a gap shape which disconnects the flow of voltage in that joint which will cause the high-pitch noise to stop.

A batch of bad ECU boards may have made it through to Nissan which may have a weak spot which could allow a cold solder joint to occur over time due to constant expansion and contraction.

09-06-2009, 11:34 AM	#13 (permalink)
ZKindaGuy Track Member Join Date: May 2009 Location: Ohio Posts: 699 Drives: 370Z-AT7 Tour+Sport Rep Power: 375	My 370Z started to have the engine bay high-pitch sound. I traced it to the area of the ECU (or ECM = same damn thing). It reminds me of a high-voltage sound that is typical of electonic circuit boards that have developed a cold solder joint (crack). Once the board heats up enough to expand the solder the joint/crack gets temporarily bridged by the solder which then will cause a voltage disparity which produces such a high-pitch noise. Once the board cools off sufficiently to contract the solder the joint/crack sides move back into a gap shape which disconnects the flow of voltage in that joint which will cause the high-pitch noise to stop. A batch of bad ECU boards may have made it through to Nissan which may have a weak spot which could allow a cold solder joint to occur over time due to constant expansion and contraction. Last edited by ZKindaGuy; 09-07-2009 at 10:37 AM.