| Message |
I'm experiencing two distinct noises which occur under different conditions. The most common noise (which occurs almost all the time) does not occur at idle. It occurs when immediately after letting off the throttle at rpm above idle. For example, during normal driving, letting off the throttle in between shifts produces the noise. If you blip the throttle from idle, as soon as the rpm start to come back down, the noise occurs. In both cases, it only lasts for a split second. In these cases, the VTC solenoids (if working properly) should be energized, and the intake camshafts should be advanced by 20°. Unplugging the VTC solenoids causes this noise disappear, which means that the noise has to be related somehow to the camshaft/gear/solenoid assembly somehow, right? If the noise isn't being caused by the gears, what else could it be? The other noise, which was not present while I was troubleshooting the other day, occurs only occasionally for a minute or two after a cold start up, and only at idle. Raising the rpm causes the noise to immediately go away. The cam gears were high mileage units (the engine they came from had 185k), so I'm almost positive this noise is do to a bad/worn gear. Do you have any other ideas as to what the other rattle could be from?
|
 |
