Hey Everybody,

I have a 2000 Disco 2 with around 160,000 miles that has been stalling while driving spontaneously lately. Usually, if we park it for a while and then try to start it again later, it works and we are able to get it home again. It hasn't thrown any codes related to the problem, but after hearing about the symptoms of a bad crankshaft position sensor, I decided to explore the possibility. I ordered a new sensor and pulled the old one (probably the original) out and discovered that the electrical connector had a significant amount of engine oil in it (presumably from last year's valve cover gasket replacement.) I installed the new sensor and now it will not start! I verified that the battery is fine, checked all of the usual fuses and relays, but everything seems in order. With the sensor unplugged, I probed and tested the sockets in the wiring harness and discovered that the power socket (which I understand should have 12 volts with the key on) on shows 1.6 volts and I am at a loss as to why?? What am I missing? What's more, I cleaned up the original sensor and tested it from direct 12 volt power and it seems to work fine. Is it as simple as the oil in the harness causing the problem? What's the deal with the low voltage being supplied to the sensor? I have looked at the forum many times over the years when working on various things that the Rover needed and have been impressed by the knowledge of many members. I finally got around to becoming a member today and actually participating and am hoping for a solution so I can get this thing on the road again. Anything you guys can suggest would be great!

 

Sounds like you got a bad sensor out of the box, it has been known to happen.

 

Get a Bosch brand sensor part number ERR7354.

 

Any thoughts on the 1.6 volts reading from the unplugged wiring harness? As I understand it, there should be 12 volts coming to the sensor when the key is on for it to work. Right?

 

I thought that it was an inductive pickup, so it generates it's own current on two wires, and the shield is the third wire.....

 

Yes, it's just a pick up coil, sensing magnetic pulses from exciter ring machined within flywheel...it does not have 12 volts going to it. Most sensors work within a 1.0 / 5.0 volt range (there are some that use higher numbers, but never 12 volts that l've seen), if they relied on 12 volts to work...everytime your voltage dropped below 12 volts...you'd be dead in the water. Most manufacturers want the vehicle to be drivable, even if the alternator quits. Now, some actuator need 12 volts to work properly...maybe cold idle solenoid or SAI motor.

 

Did you get the round spacers on Crank sensor installed correctly? If you put them in the wrong position on mounting screws, sensor goes into flywheel groove to deep...and gets bent.

 

Thank you so much everybody for contemplating this with me. After realizing that it was not supposed to have 12 volts going to it as I assumed, I decided to throw in the old one that would start it but would frequently stall after a few minutes of driving. Not easy to get those things in there, but I switched it and it started right up. I took the new sensor back to the store and had it replaced; must have been bad out of the box. The Rover is running great now! Thanks again for your help everyone!