Land Rover MK1 Disco V8 won't start.

[easy]

The ongoing saga.
Car will not start,this is the 3rd time in 5 months the car neeeded to be towed by the NRMA.First time Leads/distributer cap/pluges/coiland car was on the road again.Then 2 months later back on the tow truck again.This time replaced ignision module/full tune have the car going.Another 2months later now again car won't start back on tow truck yesterday, put another new ignition module in but to no availe.$800:00 spent to date.Had it from new 95000K to date.Any advice would be apreciated.

[Discobunny]

Check the air gap of the pickup in the dissy. I had heaps of issues with mine not starting, replaced coil, ign amp etc.
Checked air gap of pick up and reset, no problems since:D

[markyc]

Won't start: Won't turn over or won't fire up?

[wovenrovings]

Is this a 3.9V8 or a 3.5. Also what does it do? Wind over but not fire?

[RonMcGr]

Is this a 3.9V8 or a 3.5. Also what does it do? Wind over but not fire?

Daniel, I gather it winds over but won't start.

[RonMcGr]

The ongoing saga.
Car will not start,this is the 3rd time in 5 months the car neeeded to be towed by the NRMA.First time Leads/distributer cap/pluges/coiland car was on the road again.Then 2 months later back on the tow truck again.This time replaced ignision module/full tune have the car going.Another 2months later now again car won't start back on tow truck yesterday, put another new ignition module in but to no availe.$800:00 spent to date.Had it from new 95000K to date.Any advice would be apreciated.

Had a similar problem with a Jaguar once.
The starter motor was on the way out and took so much power there was not enough power left for the coil to work properly. Just a thought!

[markyc]

My 3.9 wouldn't fire up recently; turned out that the immobilizer had fallen to bits and needed re-soldering.
Run a wire directly to the coil from the battery as this removes said gizmo from the loop. If no joy, at least that's one thing eliminated...

[wovenrovings]

My dad had a 3.5 disco V8 (fuel injected) which would become very very hard to start after sitting for about a week. It appeared to wind over with more than ample speed and had spark. However it would start and sometimes it would go just as you would let go of the key. Usually we had to push it down the hill. On several occasions it ran backwards for several turn on letting go of the key after trying to start it. Battery voltage seemed fine while cranking.
When we went to sell it dad put a new battery in. Fixed it. The old battery has worked for a couple more years in the 88" since.
My theory is that the voltage was some how affecting the computer which would then not put fuel in. Worth a try.

WR.

[easy]

Thanks Guys
3.9 V8 motor turns over fine on starter motor (new battery to) will try
jumper from battery to coil & see what happens.
How do you reset air gap Discobunny. Is their a way to check if the ECU is behaving?

[damienb]

My 3.9 wouldn't fire up recently; turned out that the immobilizer had fallen to bits and needed re-soldering.
Run a wire directly to the coil from the battery as this removes said gizmo from the loop. If no joy, at least that's one thing eliminated...

If it's the right year, it will also immobilise the fuel pump and/or crank. This is one of the first things I would suspect also. Any one of the circuits can fail, or all can fail. What year is it?

/Damien

[easy]

damienb
Its a December 1998 build, so its still OK to run a wire from + battery to + coil
to by pass imobiliser. Failing this where would some one recomend a LR mechanic in the RYDE area?

[damienb]

damienb
Its a December 1998 build, so its still OK to run a wire from + battery to + coil
to by pass imobiliser. Failing this where would some one recomend a LR mechanic in the RYDE area?

It's a spidy year. Battery to coil will check the ignition immobiliser. I guess spraying starter fluid in the inlet while cranking will check the fuel pump (or use a multimeter). It's a relatively easy fix - easier than the forums indicate. Pull the dash apart until you get to the spider, rip it out, and either re-solder, or bypass. Throw it back together, and it should be good. It took me about 2 hours. The worst part is that 10 year old plastic is not particularly strong, and a lot of tabs break off. Superglue works well to reassemble.

A bit more info here: Definitive Alarm Spider Post........ this may come in useful!! - DiscoWeb Message Boards (http://www.discoweb.org/forums/showthread.php't=9316&highlight=spider+1998)

Someone else might help on the mechanic.

/Damien

[Bazzle218]

My symptoms werethe same. 3.5 efi disco 1 . Spent $900 on getting things checked out by an efi specialist. Turned out the plugs i put in were crap can't recall what brand. Had spark all the way but at the end of the plugs.???? Gremlins. Anyway replaced plugs and went well. Another thought is it possible that one or more of your injectors are leaking over time and flooding it hence winding kick and stop ect. also had starting problem after sitting. Out of shear frustration put a set of injectors out of Commodore vp in and beast now starts and runs better then it ever has. Sure to get shot down by someone more knowledgeable but for the price of a set of decent set of plugs who knows. Happy trails Baz:D

[RonMcGr]

Bazzle218,

He has changed them.
I've had probs with plugs before.
Heat can destroy them very quickly.

[Freestyler]

Hi check that the fuel pump is working, I had this happen in the drivway at home, the fuel pump died. There is also an inertia switch that cuts the power to the fuel pump in case of an accident. It may have triped for some reason or failed. It is on the RHS under the dash to the left of the steering column. (91 disco) it should have 2 wires going to it white and white with purple strip. You can just short it out to test it. I have had mine in my county do it on very rough road up in the NT. Tim

[Discobunny]

How do you reset air gap Discobunny.

First of all, have you checked if you are getting any spark?? Is it weak??
If you are getting a good fat spark, you have other issues.

Anyway, Air gap check as follows.
Pull off the dizzy cap, remove the rotor and shield.
You will see a reluctor ring monted on the shaft, this has eight points to it.
There is a magenetic pickup in the dizzy, as the shaft rotates, the points on the reluctor ring pass really close to the pick up and influence the magnetic field which then sends the signal to the amp, etc.
Turn the motor over by hand until one of the points on the ring is next to the pick up, the gap should be 0.2-0.35mm from memory, mine was a little over 0.4mm and was enough to give weak intermittant spark when cranking.
Get your feeler guages out and check the gap. I adjusted mine to the minimum 0.2mm.
I'm sure Blknight will correct any errors in procedure or terminology in the above, thanks Dave:D

[chazza]

Have you checked the connections in the low tension circuit? Mine played up for a year at least, until I squeezed one of the female connectors on the coil with a pair of pliers. The connector seemed to be a particularly poor design and didn't really grip the tag very well.
No more problems 2 months later:D

Cheers Charlie

[easy]

Well finaly got to car last night, their is no spark from coil,changed coil still no spark, checked all connections, nothing,have bypassed spider,still nothing, put a new battery in, nothing.It's getting to the piont I have to get a specialist LR to fix,any recomendations I'm in the Ryde area Sydney. Help, I have had this car from new 90000k no problems untill the last 4 months.Thanks fellas