check engine light on 2003 Ford Explorer

check engine light is on. When driving and parked makes chirping noise. Also in park rpm's go up then down.When shutting off makes a quick whining noise when engine shutting off. Could this be a belt, (Camshaft syncronizer)????

2 answers
This vehicle has a 4.6L engine, so it should not have a camshaft synchronizer. The chirping noise could be the serpentine belt or the tensioner for it. It could also be the AC compressor, turn the Climate control completely off and see if the symptoms still exist if not there is an issue with the AC compressor the clutch. In rare cases a very bad tensioner can cause the check engine light to come, it causes smilar vibrations to the engine misfire and the engine control module can be fooled, but like I said it is rare. You can remove the serpentine belt and run the motor for a short time to see if the noise goes away, if it is still present you could have a vacuum leak. That would cause similar symptoms. You may need to have the engine control module scanned and then diagnosed to repair the check engine light.Good luck.
my explorer does the same thing the engine light is on. 4.0l v6