RE: unclefestives post.
I also had that challenge. After seeing the Service Engine Soon light come on, we decided to access the DTC (diagnostic trouble codes). Those codes really are a huge help in pin pointing where the trouble is coming from!
We had a good friend of mine who was a certified mechanic replace the crank angle sensor, but he did his best to eyeball it as there is a alignment tool that is needed, and he didn't have access to one (it wasn't his fault truthfully, we needed the car to run, and knowing that it was probably not aligned correctly, we went ahead anyway). Two months later the sensor failed, and we ended up taking it to a shop where they had the alignment tool and properly placed the sensor. I saw the tool available on ebay for a very reasonable price, and although the PAU is running great now, I was tempted to get it....just in case...lol.
I thought I would also share this experience...
Just recently, the engine threw a code 42 (cam angle sensor). Until we removed the sensor (it was cracked) and replaced it, we found the engine ran really rough. Apparently when there is no signal from the sensor, the PCM fires the cylinders at random, with and I quote the shop service manual "a one in 6 chance of firing in the right order". My research also found that the magnet that activates the sensor (located on the cam sprocket gear) sometimes will fall out, resulting again in no signal generated. While we had the cam sensor off, we rotated the engine until we could verify that the magnet was intact and undamaged. Once we replaced the sensor, the car ran better, but after a day, the engine wouldn't start. Long story short, we found out about the infamous Intake Manifold Gasket fiasco (poor design in material selection, so the stock gasket leaks water into the cylinder(*) ) and after changing it out, now Betty (the affectionate name we give the PAU) runs like a champ. If there is going to be any lower engine trouble as a result of the leaking gasket and the water that was in the cylinder, I guess we will find out.
So far though, she runs silky smooth now.
Just my experiences as related to the crank angle sensor.