Guys what does this sensor actually do? What are the symptoms if it needs replacing?

Moved topic to a more relevant place - but what does the cam angle sensor do? I would imagine it would just confirm to the ECU the angle the cam is at in relation to the crankshaft - RE BA / BF VCT, since the VCT is able to vary the cam retard / advance angle within a certain set of limits.

Don't know what the symptoms of a crook one would be - what are you experiencing & what vehicle are you referring to?

usually car wont start without one. what car are we talking about?

Basically the cam angle sensor tells the ECU where the engine is in relation to firing order. EF has two crank angle sensors, one on the front harmonic pulley and the other where the dizzy used to live. AU has one on the front of the engine

Remember the cam-angle sensor does a different job to the crank-angle sensor, as the cam angle sensor measures the amount of advance or retardation of the camshaft due to the VCT operation...

I have an EF on Gas...the computer says it needs replacing.....it seems to be running rough.....What if the plenum box/air intake thingy??? gasket needed replacing....when i did the head up recently i had to split the air intake and just reused the old gasket. Could that be an issue?

if it was the original steel one then unlikely. but a paper one would affect it

EF running rough with a cam-angle sensor fault? Not sounding good...start with a compression test to check for bent valves. Hate to think that the cam gear had jumped a tooth - Shane is this possible without destroying the engine? - Is it something that happens on these?

never seen one jump teeth, althou it is possible to set it up wrong as per experience in rebuilding XR engine

Could start to give some clues - when did the problem start? Was it present before you did the head up?

RE manifold gasket - if it is the steel gasket you are talking about, while I haven't heard of one leaking, they do lose their elasticity over time and flatten out. It is possible that this might be leaking...at least one member on here has had his rough idle solved by replacing the manifold gasket - but in his case it was the gasket between the manifold and the head that was the problem, not the gasket between the two halves...

Yep, intake manifold gasket fixed my rough running EL, although as Duggy said it was the gasket between manifold and block.

Other things to look at - Leads and plugs are a good start, if you haven't already. ISC gets dirty and a clean sometimes helps, there is instructions on cleaning it here somewhere which I'm sure you could find if you did a search. Dirty injectors, a couple of bad batches of fuel can be enough to clog them up. I've heard of people solving it by replacing fuel filter for the same reasons. Other than that, look for other possible vacuum leaks, and perhaps try a computer reset.

...just some further thoughts - have you been through all of the vaccuum connections after the head rebuild to make sure they're all attached properly? Easiest thing to do and quickest repair to make (at no cost to yourself) if wrong... Start with the easy stuff first I say!

I know this is an old thread.. but I had to post.

Cam angle sensor tells the ECU where the engine is exactly in the 720º revolution in a 4 stroke design. Because the crank turns at twice the speed of the cam(s) there's no way to tell from just the crank position whether No. 1 is TDC firing or TDC exhaust. All the crank sensor tells the ECU is that No. 1 piston is TDC but that could be TDC compression/power or TDC exhaust/intake.

Motorbike engines, even 4 stroke, do not have cam angle sensors - they just fire on every TDC with a redundant spark.

Fat tony is correct.
In fact the terminology is actually incorrect. It's actually a CID (Cylinder Identification) sensor for the reasons tony said and only has one pulse per camshaft revolution, it signals the start of fuel injection event. On Sequentially injected engines(ie the AU 5.0) it is therefore more critical in the injector firing events. It is less critical on bank fired engines(the 4.0L) but still has some effect because obviously cyl 1 would need to be in the first bank(injectors are fired in 2 groups of 3) of injectors fired.
A cam angle sensor is used on engines with VCT so the EEC has feedback on the actual position of the camshaft.

My car Check Engine light has been coming on & off for a little while. When I took it to my local AutoZone, they told me it was the Camshaft Position Sensor, and if I didn't replace it soon it would eventually make my car not start.My question is, I'm about to go on a roadtrip & I didn't know if I could drive it like this or if it should be taken care of before the trip?thanks