My 2003 Discovery II recently has been not starting at times. I let it sit for a little bit (sometimes a minute, sometimes 10 minutes) and then she'll start up again.

It cranks absolutely fine, in fact it cranks for quite awhile when she won't start w no signs AT ALL of a low battery & the charging system is dead on 14V.

I attached a fuel pressure gauge to the valve behind the intake & positioned it so I can see the psi reading from inside the car... When she wouldn't start it's right in the 50-52 psi just like the manual says it should be, but I'm not sure if it's bc it's holding the pressure from previously...??

Any ideas where or what to check next...??? Thank you for any help.

 

possible crank shaft position switch

 

Is there anyway to check besides just replacing...??? I was just in there myself doing a timing belt over the summer.

 

Easiest way.
Run the vehicle til its hot and shuts off, then dump water onto the crank sensor. if the car starts, its you problem.

Hardest way.
Removed the crank sensor and attach leads connected to a multi-meter in the Ohm range. place the crank sensor in a pot of water and heat it up while observing the readings. when it s gets hot and the reading goes from for example 0.2 ohms to O.L. you have found your problem and effectively tested a crank sensor.

 

if you have an obdii scanner that reads live information, switch the scale to RPM if you get 0 while cranking the CKPS is bad.
NO you can not use the tachometer in the truck.

 

My fathers scanner does show live data, so we went into engine speed (rpm) to watch what happens w no start / stall. Running idle it did stall / die and would not start again. Fuel pressure gauge dropped to 40 and kicked the scanner offline / no communication. All the dash lights still worked and so did cranking (except no start). Further investigation points to Main relay...??? Swapped it out for a new / used relay and she started right up. So far she's been running for 1/2 an hour idle and no stalling. Going to take it for a spin to get lunch and see what happens. (fingers crossed)

 

Not sure what you mean by "main relay", but I had similar symptoms when my fuel pump relay failed.

The fuel pump relay and crankshaft position sensor have very similar failure symptoms.

 

Main Relay is located in position # R9 under the hood. If you pull it everything on the dash still lights up and the car will still crank since those are both controlled by other relays. R9 also controls the ODB port which is why I was booted offline with the scanner as soon as she stalled. That was the clue to lead me to checking R9 out. It definitely felt extra hot to the touch. I changed the relay out today and haven't had any stalls so far w 15 miles of driving and about 3+ hours of ideling. Before swapping the relay she was stalling and not starting quite often / progressively getting worse and worse. It hasn't done it yet. My fingers are still crossed and I'll report back if it does in fact hold.

 

Ok, relay didn't do the trick. It is now no start at all. Went into scanner and opened up engine speed graph and getting nothing at all with cranking. New Crank Sensor is on the way.

 

This thread may help if you are a bit crazy:

https://landroverforums.com/forum/di...e2/#post443936