Vehicle Information:

• Make and Model: 96 Land Rover Discovery
• Engine: 4.0L V8
• Mileage: 128,XXX Miles

General Information:

• Limited Automotive Knowledge
• Fuel Pump Replaced 1k Miles ago
• Alternator Replaced ~1k Miles ago
• Fuel Pressure Good, and fills the rail
• Battery Holds Charge/Cold Cranking Amps
• Alternator Produces Proper Power
• Check Inertia Switch - good

The Problem:
Intermittent Issue: I go to turn the key, the engine tries to start, cranks, but will not turn over. I have pulled wires on the plugs to see if there is spark the result: no spark.

Everytime I take it to a shop to get diagnosed, it starts just fine...

Remedies: - Some of this might just sound insane but it works occasionally...

• I have hooked just the negative batter post up to a jumper cable - it has worked and it hasn't worked
• I have grounded the negative to my frame - it has worked and it hasn't worked
• I have grounded the negative to the engine - it has worked and it hasn't worked
• I have pulled all of the fuses - it has worked and it hasn't worked
• i have pulled just the fuel pump fuse - it has worked and it hasn't worked
• I have put the disco in to gear - it has worked and it hasn't worked
• I have rolled down my window - it has worked and it hasn't worked
• I have rolled down all four windows - it has worked and it hasn't worked
• I have open and closed a door - it has worked and it hasn't worked
• i have unlocked the disco via key three times - it has worked and it hasn't worked
• I have unlocked the disco three times via the fob - it has worked and it hasn't worked
• i have locked and unlocked the disco 3 times by key - it has worked and it hasn't worked
• i have locked and unlocked the disco 3 time by fob - it has worked and it hasn't worked
• Wait an hour
• Jumping the car always seems to work

Things I have read on forums and think could be related:

• Security System shorting, needs to be taken off of auto arm by dealer/service shop
• Crank Shaft Position Sensor
• ECU Replacement... (I really hope not)

Anything sound reasonable?


Any help would be greatly appreciated!!! I am so frustrated.

 

If jumping always works, you need a new battery(at least). What do you mean it cranks but will not turn? If it is not turning why you expect a spark?

 

By cranking and not turning over I mean the engine is trying to start, but wont run. I guess

 

You may also try cleaning all the battery terminals, both the post on the battery and the insides of the lugs from the vehicle. Just hit em up really good with some sandpaper, even if they appear to be clean. This fixed a very strange starting problem for me once.
It may not fix it, but it will cost you nothing to try.

 

Where are you checking the spark?

You can check if there is spark in the coil and in tip of the cables that go to each spark plug. If there is no spark in the coil, then the coil may be not working or it may have a bad contact somewhere. In the distributor, disconnect the tip of the cable that comes from the coil and ground it against the chassy of your car or engine. Then disconnect from the coil the other tip of the cable and check if you have spark. If there is always spark, the problem will be the distributor cap and/or Rotor.

Take out your distributor cap (try to not disconnect the cables, or identify them if you will disconnect them) and check each pin for wearing. Also check the tip of the distributor rotor for wearing. I had a similar problem and the replacement of the distributor cap solved the issue.

If you find that there is no spark in the connection of the coil, let me know. I can help you trough the electrical diagrams in order to try to isolate the problem.

 

Isn't the 96 4.0 solid state ignition like the 97 4.0? What rotor and cap? You're thinking about the 95 3.9 I believe.

 

johnkbl, I have the 4.0 that Danny Lee is talking about, no such luck with the distributer... I have one of those odd Coil Packs - http://www.roverparts.com/Parts/ERR6269ABP.cfm thanks for the response tho!

 

Illiminate the battery issue first by having your truck tested at a local parts store, voltage should btw 13.6 and 14.4 volts. If it is OK, then you most likely have a crank sensor starting to fail.

 

Check this out also. Has to go to the dealer for this because it is accessed by Testbook..

 

I don't think the attached pdf applies to his model 96.