2000 XJ Camshaft Position Sensor Test.

I searched this already.

Looking to test the Cam Pos. Sensor along with Crank and Knock. Can find test info on the crank (engine off, should show open), but not the cam or knock. Am I looking for an open on these other 2 sensors like the crank? Or am I looking to test voltage, resistance while ignition is on? If so, could you tell me numbers there?

Thanks,
Tim

You dont have a knock sensor on your 2000....

I dont really think you can test a Crank Pos Sensor....it either works or doesnt...it will throw a code if its not working properly.

Actually I do. It's above the the upstream O2 sensor. Also, you can test for a functioning or malfunctioning crank sensor by testing impedance. If you show open on you DVOM it functions properly. If anything but open, it's defunct.

Well, then you have some kind of weird mod on your 2000, b/c my 2000 doesnt have a knock sensor....i just have 4 O2 sensors....2 before the pre-cats, 2 after....

Knock sensor was deleted with OBD 1. It was only used with Renix rigs, am I right?

Dunno what he has without a picture!

Not sure of the testing procedures for the CAM sensor.

Testing the crank sensor alone is not enough. It can work sometimes, but not others......so it's not like once it goes bad, it stays bad.

Apparently I have a funky setup and maybe that's part of the problem. No if's, and's or but's it's up there. Thanks for the heads up Blaine. I have had 2 misfire codes in 2 weeks on 2 different cylinders with poor mpg. Not a wiff of 02 codes, everything I come across puts it as either the cam or crank shaft in all likelihood. Coil has been checked, plugs done, air filter in, tps and iac cleaned. Figure all bases should be covered. Rough warm idle, with cutout at 50-75mph. Oil pressure has been surging to which leads me to believe that the cam ps might be bad too. Just not sure on the cam if I should be looking for an open or the .03-.5. Thanks to all.

The Camshaft Position Sensor (CMP) on the 6-cylinder engine is bolted to the top of the oil pump drive shaft assembly. The sensor and drive shaft assembly is located on the right side of the engine near the oil filter.

The CMP sensor contains a hall effect device called a sync signal generator to generate a fuel sync signal. This sync signal generator detects a rotating pulse ring (shutter) on the oil pump drive shaft. The pulse ring rotates 180 degrees through the sync signal generator. Its signal is used in conjunction with the crankshaft position sensor to differentiate between fuel injection and spark events. It is also used to synchronize the fuel injectors with their respective cylinders.

When the leading edge of the pulse ring (shutter) enters the sync signal generator, the following occurs: The interruption of magnetic field causes the voltage to switch high resulting in a sync signal of approximately 5 volts .

When the trailing edge of the pulse ring (shutter) leaves the sync signal generator, the following occurs: The change of the magnetic field causes the sync signal voltage to switch low to 0 volts .

Blaine B. said:

Knock sensor was deleted with OBD 1. It was only used with Renix rigs, am I right?

Dunno what he has without a picture!

Not sure of the testing procedures for the CAM sensor.

Testing the crank sensor alone is not enough. It can work sometimes, but not others......so it's not like once it goes bad, it stays bad.

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x2

tbrunson said:

Apparently I have a funky setup and maybe that's part of the problem. No if's, and's or but's it's up there. Thanks for the heads up Blaine. I have had 2 misfire codes in 2 weeks on 2 different cylinders with poor mpg. Not a wiff of 02 codes, everything I come across puts it as either the cam or crank shaft in all likelihood. Coil has been checked, plugs done, air filter in, tps and iac cleaned. Figure all bases should be covered. Rough warm idle, with cutout at 50-75mph. Oil pressure has been surging to which leads me to believe that the cam ps might be bad too. Just not sure on the cam if I should be looking for an open or the .03-.5. Thanks to all.

Click to expand...

Sounds like a crankshaft PS to me. That's what happens when they start going bad. Mine did that. Camshaft PS rarely go bad.

If you're still getting bad gas mileage after replacing the crank sensor, go after the oxygen sensor. I've heard they sometimes don't throw codes because they aren't "bad" enough to throw one....but still, bad.

Take a picture of this "knock sensor" look-a-like. Would like to see what this is. When you get a chance to, of course.

My sincerest apologies J. and Blaine, it is an O2 sensor up there. Just has an odd connector up there. Although from what I can read, the OBDII start didn't wipe out the knock sensor at the close of OBDI 100% of the time. By way of impedance testing this thing is my crank sensor at the least (not my words. Cam tested fine. It's on order and afterwards will keep my eye on mpg of course in regard to O2 sensor. Thanks.