Hi, a neighbor of mine has a 2002 Discovery which she says has trouble starting, then runs pretty rough when it does staart. From what I've 'garnered' on this informative forum is that the issue may be the Crankshaft Position Sensor.

My question is this: Is there a way to test the CPS on & off the vehicle? For example, what test voltages or resistances using a multimeter should I be reading? Or, could you pull it off & check it (or take it to say, Advance/AutoZone to have them test it?). Or...is there another way?

Anyway, I haven't yet gotten my hands onto the vehicle, so I'm flying a little blind. If you have any thoughts on problems endemic to these vehicles, I'm all ears.

Thank you.

 

maybe the MAF is bad? When mine died it did the same thing. Is your neighbor easy on the eyes lol

 

The CKP sensor is a coil of wire, and it produces a signal when the reluctor disc passes by the tip. You would need an oscilloscope to see it. If you go to enough trouble to pull it out, you may as well change it. Plug it in and let it hang down, then re-attach. About $70.

Usually a bad one won't let you restart when hot, has to cool off. Wouild be good to know what engine codes might be in there, get a free code scan at parts store.

 

And here are some pages and volts on the sensor.

 

I appreciate the help & will run with it. I'll let you know how it goes.

 

I'll check out the MAF, as well. BTW, she's not bad for a lady in her 70s!