What's killing my ignition?

[markyc]

Guys,
One of those intermittent PITA problems..
Very occasionally my '96 V8i refuses to fire. Turns over fine, just no attempt to start whatsoever.

It seems to happen when warm, like after a run then a quick stop/start, for example: Pull up to bowser. Turn off. Fill up. Start and drive 10 meters to air line or parking spot. Turn off. Then no go for 10-15 minutes, then starts as normal.

Last night it actually died whilst driving; 500 metres down the road (from a cold start this time), battery light and instant death. I let it stand for a while and it fired up, ran 500 metres and died again. When running I had a strong blue spark to the dizzy and no visible tracking anywhere.

After another spell I made it home and have driven in to work this morning with no dramas but don't we just know it'll happen again? Any ideas?

[almoc]

This happened to me on and off for a some time. Replacing the spider cable seemed to eliminate the problem. This was in a 99 series 1 v8.
If yours hasn't been replaced it is probably due anyway.

[markyc]

Within the last year I've replaced the plugs, leads, cap & button (with Bo$ch/Luca$!) so I'm thinking elsewhere..but where? Ignition module on side of dizzy seems to come up in topics now and again..

[Michael2]

I had similar symptoms in the EFI RR sortly after fitting LPG. The LPG installer had removed the main fuel tank to fit the LPG tanks and extended the wiring on it to reach the aux. tank position. There were about five cuts and joins in the wire and none were soldered:mad::eek:.

The car ran on LPG, but not on petrol. I couldn't start it though as it starts on petrol, unless I roll started it:eek:. It played up in Port Augusta, as I was driving Perth to Melb, and thinking it was the fuel pump I fitted an external EFI pump from a Commodore. When I got home and pulled it apart I realised it was just voltage drop to the main pump.

Anyway, the moral of the story is :

You may have an intermittent fuel pump or dirty wiring / earth at the fuel pump.

[Diff]

My F100 had a problem like this would drive fine but would not fire after stopping after a 10minute drive. Wait half an hour and it would start fine. Drive for hours fine. just wouldn't restart when hot. After nearly $800 we found that there is an internal wire coil in the distributer that had a small crack. When it got hot the gap expanded and no starty. When cold again no gap and no problem.

Don't know if this helps but in confuse the mecanic and me for months.

[markyc]

Ok, so during the next episode I need to establish fuel or spark problem, yes?
Any tips for road side tests? I have a multimeter and I'm not afraid to use it:D

[101RRS]

MarkyC - I can almost guarantee it is the ignition module if it is still on the side of the dizzy. They are realatively cheap at around $100 but the problem will come back. They cook with the heat. Carry a spray bottle of water to cool the dissy down and it will normally get you going - in heavy traffic having the bonnet popped also helps but you will need to lock it when going faster

I moved mine to the area near the coil like the later D1s have - wasn't easy but I think you can now get a wiring loom and mounting bracket that will do the job but not sure from where.

Garry

[Michael2]

Ok, so during the next episode I need to establish fuel or spark problem, yes?
Any tips for road side tests? I have a multimeter and I'm not afraid to use it:D

The fuel pump only works when the motor is running or being cranked, so you'll need someone with an ear (or stethoscope) to the tank, listening for the pump.

If it's not going (or you can't hear it) unplug the pump wire and see if it gets 12V while you're cranking. This tells you if it's getting power from the relay, now you can isolate the fault to the pump, or the electrical relay that feeds it.

If there's no power from the relay, you can run a positive from the battery to the pump side of the plug and ensure that that still works. With the car off, you should be able to hear the pump.

It's a bit fiddly, but half an hours effort should eliminate it as a cause before you go & spend $$$$ on the ignition module.

To test for spark, put a spark plug on a lead, rest it against earth (-ve ie: motor) and crank the car. If you have spark, then your ignition is working (at least intermittently).

Other things that may cause this are an immobiliser or alarm. Are these likely culprits?

[incisor]

ignition module....

[matbor]

It will be the ignition module or fuel pump, have a listen next time you have the problem.

[LandyAndy]

Ignition module,hade an XE Falcoon that did the exact thing.Bought a new module but didnt fit till it next happened.When it did,swaped them over never happened again.
Andrew

[Bigbjorn]

The classic electronic ignition failure is a sudden stop when hot. Then will restart after cooling down. May not re-occur for some time. Generally stoppages become more frequent and waiting periods become longer until total failure occurs. Nearly always undiagnosible at roadside. The usual symptom is no spark and no bloody way to find out why. Take it to the dealer and nothing is found wrong as the bloody thing is now working perfectly until next time. This is why I drive a County-Isuzu with no electronics whatsoever.

[4bee]

I understand that the use of Thermo conducting paste between the module & the Dizzy body, is supposed to minimise this due to the transfer of heat away from the Module to the casing.
Trouble is, it seems a bit of a bugger to get any in there without removing the dizzy to access the module. Ho hum.;)

[Utemad]

I understand that the use of Thermo conducting paste between the module & the Dizzy body, is supposed to minimise this due to the transfer of heat away from the Module to the casing.

This should always be used on any heatsink. You can get a tape which does the same thing but don't know how effective it is.

I had a Commodore (81 VH) which had the same problem and it was also the ignition module.

[101RRS]

Heatsink stuff will not make any difference The module gets its heat from from the engine - it sits on top of the block on the side of the dizzy and is in between the heads - as well, from the heat from the radiator flowing back over the engine. The module fails not from the heat that the electronics generate but the heatsoak from the engine.

Garry

[Utemad]

Heatsink stuff will not make any difference The module gets its heat from from the engine - it sits on top of the block on the side of the dizzy and is in between the heads - as well, from the heat from the radiator flowing back over the engine. The module fails not from the heat that the electronics generate but the heatsoak from the engine.

Garry

I agree but when you move its position wouldn't you bolt it to the body and then the body would become the heatsink? (electrically insulated from the bodywork too I'm guessing?)

I haven't moved mine but I'm thinking I should. My brother had no end of trouble from his in his V8'ed FJ45 until he moved the module. Now that is a vehicle that doesn't need a heater in winter!

[101RRS]

I agree but when you move its position wouldn't you bolt it to the body and then the body would become the heatsink? (electrically insulated from the bodywork too I'm guessing?)

I haven't moved mine but I'm thinking I should. My brother had no end of trouble from his in his V8'ed FJ45 until he moved the module. Now that is a vehicle that doesn't need a heater in winter!

Your right in that scenario - I moved mine to the area near the front left headlight and used a jaycar heat sink. I had no problems after that.

Garry

[4bee]

I can see that happening, Garry. The idea was that heat from the module flows to the dizzy body, but as the body would be as hot or hotter, being in the front, I can appreciate what you are saying.
I haven't done it or moved mine, but then I haven't had a problem.


Yet!:D

[101RRS]

I can see that happening, Garry. The idea was that heat from the module flows to the dizzy body, but as the body would be as hot or hotter, being in the front, I can appreciate what you are saying.
I haven't done it or moved mine, but then I haven't had a problem.


Yet!:D

I don't want to jinx you.

I bought my Disco new in 94 and in 98 it started playing up but not when hot but on cold winter Canberra mornings - the car was in and out of dealers, specialist and mechanics - most said it was a faulty ECU - it wasn't. Wasn't until 2003 (5years of having this problem) that it started playing up when hot - as someone said it gradually gets worse. Mine must have developed a dry joint inside that first showed up in the cold then finally when hot. It was when I was driving in Sydney in peak hour with a car trailer in tow on a hot day they brought everything together. I ended up at an auto electrician who had never seen a disco before who pinged the issue - he said lasers used to have the same issue and said it was the ignition module. He couldn't fix it on the spot but said to drive with the bonnet popped and when it stops put some water on it - it worked.

I put in a new module but it failed in about a year in the hot weather. I then made up a harness that was difficult as I couldn't get the correct connectors and had to make my own out of plastibond - I mounted the module at the front of the car where the later models have them mounted and it worked a treat.

As I said - I don't want to jinx you but my view is that like a lot of landrover issues, it is not a matter of IF but WHEN but the fix is easy with the harness.

Garry

[4bee]

This is reminiscent of the "V8i poor idle problem". Simple fix in the end (in my case) was clean & reset the AFM Multiplug pins.;)

Can one purchase a harness to shift this to the front now? Seems so. Any details?

[101RRS]

This is reminiscent of the "V8i poor idle problem". Simple fix in the end (in my case) was clean & reset the AFM Multiplug pins.;)

Can one purchase a harness to shift this to the front now? Seems so. Any details?

I think it was late 96 or early 97 that the ignition module was moved off the dizzy on all 3.9 discos - I suspect can be purchased from a wrecker or aftermarket landy parts supplier.

[4bee]

Thanks, Garry.:)

[markyc]

What does this module look like?
My dizzy has two wires appearing from it's side which join a connector block then disapper under said dizzy in the general direction of my coil..
I'll try and get a photo later.

[101RRS]

This is it - it plugs in and bolts to the side dizzy - sorry a little out of focus.

The power comes in at the top.

[markyc]

Er, never seen that before!
I'll have a scoot underneath and see if I can find it..

[101RRS]

Er, never seen that before!
I'll have a scoot underneath and see if I can find it..

It is in the side of the dizzy - maybe you have a later version and your module is already mounted at the front of the car near the coil.

[markyc]

Right..bought new module and fitted it today. Started first time:) and then quit again earlier tonight:mad:
RACV guy ran a wire from +battery to +coil and away we went! He said something about a 'power drop' or maybe ignition switch acting up..any thoughts before i blow more dollars? Or a blood vessel?

[markyc]

Pop! splat!
Er, first aid kit anyone?