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.

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. 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

[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

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.