Discovery startmoter running, sometimes engine wont start

Hi, Any ideas, My Discovery V8, 99 Automatic does sometimes not start. The startmotor is running but the motor does not take it. No alarm lights whatsover, so I guess the fuelpump or the power to the fuelpump. Anyone know where to look for broken cables?

fingigs said:

The startmotor is running but the motor does not take it.

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Needs clarifcation.
Does this mean the engine is cranking over but not starting?
Or the starter motor is running but not turning the engine?

Are you saying the engine turns over when the starter motor runs, but the engine will then not fire up / continue ?

Edit : Great minds think alike - lol

Stanleysteamer said:

Needs clarifcation.
Does this mean the engine is cranking over but not starting?
Or the starter motor is running but not turning the engine?

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The last

Pawl said:

Are you saying the engine turns over when the starter motor runs, but the engine will then not fire up / continue ?

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Haha.. the startmotor is running. but the engine wont start.

If the V8 works in a similar way to the TD5 this could be interference to the crank position sensor feed. Sometimes when the contacts in the starter solenoid are badly pitted they can cause arcing which can produce electromagnetic interference which in turn can interfere with the output from the crank position sensor. On the TD5 if that signal is degraded the ECM will not allow the engine to start. It catches a lot of people out as the starter is turning over fine and is rarely suspected of being the problem. A diagnostic check will show if there is a crank sensor issue and if so, a £10 solenoid refurb kit will fix it.

Si Click said:

If the V8 works in a similar way to the TD5 this could be interference to the crank position sensor feed. Sometimes when the contacts in the starter solenoid are badly pitted they can cause arcing which can produce electromagnetic interference which in turn can interfere with the output from the crank position sensor. On the TD5 if that signal is degraded the ECM will not allow the engine to start. It catches a lot of people out as the starter is turning over fine and is rarely suspected of being the problem. A diagnostic check will show if there is a crank sensor issue and if so, a £10 solenoid refurb kit will fix it.

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Thanks I will look into that, It could also clarify why sometimes it will start only after moving the gearhandle or pressing the breakpedal.

What may be of importance, the up-downhill adjustment light lights up shortly sometimes when I try to start it.

OMG! Its even worse now. while driving for 5 minutes there was a hikup in the engine. After that the 2 greenlights with M and S in a gear started blinking. I hope it is still the fuelpump and not something in the gearbox.

If you get the M&S lights again check to see if the MIL (engine check light comes on) if the answer is no, then check the battery voltage and check the battery terminals for security. If I have counted correctly there are 31 possible causes of the M&S lights, but on the second cycle of the fault only one does not light the MIL - battery voltage below 9V with the engine running. On a TD5 low battery voltage will also inhibit start even if the engine turns over, not sure about an injected V8. If the MIL is on then get a diagnostic check as there are 30 possible causes and you don't want to waste time or money on the wrong one.

Thanks, that could be the fault. Maybe its also a murphy's together with the XYZ switch. Ive been having problems with that some longer time. I'll check the battery and the switch.

fingigs said:

Thanks, that could be the fault. Maybe its also a murphy's together with the XYZ switch. Ive been having problems with that some longer time. I'll check the battery and the switch.

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The battery terminals are a complete abortion.
It is best to partially tighten them OFF the posts then hammer them down onto the posts. Only way I have found of being sure they are on tight.

Thanks everyone. Just dropped her off at the repairshop. Ordered a fuelpump and fuelfilter, also the XYZ switch is coming of to be cleaned and the battery is going to be checked. Lets see...

Are they doing a diagnostic check?

Si Click said:

Are they doing a diagnostic check?

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Hi, been a while. I ordered a new fuelpump and it is replaced. We checked for oilleaks while suddenly the motor stopped. Would not start again. The diagnostics showed a fault in the camshaft sensor. P0335. Or was it the crankshaft? Anyway. I have a spare motor and took them off it yesterday. Monday they will replace the sensors. Lets see...

I suggest you read post #9 again.

I know I know. Fuelpump was already ordered so I went first with that.

At least they are easy to fit on a D2. A Defender is a right palaver.

There is no stand-alone fuel filter in the Disco 2 V8. The only fuel filter is built into the fuel pump itself.
I bet your troubles are from a low voltage battery and a bad crankshaft position sensor. Make sure the garage replaces it with a Bosch brand.