Intermittent Ignition Failure

[Stagless Steve]

I first posted about this on 8th August (Crazy Tacho and Missfire) and thought I had fixed it. Obviously not as it died on me on Sunday! It’s been mostly fine since early August but on Sunday the engine just died as I was driving along. The Tacho dropped to zero and the ignition warning light came on even though the car was rolling along with the car in gear, so I think it has to be ignition related rather than fuel supply.
I stopped, turned the ignition key and it fired up again. Drove about another half mile and the car died again. This time it wouldn’t re-start, so I fiddled about under the bonnet, tried firing it up a few times until eventually it fired up again and got me home.
In my previous post a number of helpful people mentioned that it might be the electronic ignition playing up. Below are some photos of my set-up. The previous owner has told me it came from Power Spark. I guess it would have been fitted between 5 and 8 years ago. The +ve lead is connected to the inertia switch feed (as someone suggested).Does anyone have experience of problems with this type of system?

Steve

[Staggard]

I had the same problem with a Powerspark lasted just under2 years and a Accuspark lasted under 2 weeks. After stopping it fired up a went for a couple Klms before finally dying. I then decided to reach a bit deeper in the old pocket and buy a Pertronix never missed a beat since, should have done it sooner and saved myself all the agro.

[wilf]

Definitely worth checking the condition of every connection and wire around the spark box before condemning it. Apart from anything else, it is the "cheapest route to a fix" potentially.

The tacho dropping to zero shows it is on the LT side.

[V Mad]

A couple of observations, there is no earthing wire.
The gap between rotor and red module could be closer.
Where was the red power lead connected to?

[big lad]

Thats deffo your electronic ignition, I had the same as you .It cut out and backfired , then started ok and ran ok for about a month, then on my way back from a car show in Wales, it cut out and after a few minutes would start up and run for about half a mile then cut out again.Did this about 3 or 4 times,so called the AA. At first they thought it was the coil, so we fitted a spare coil I had in the boot, but it did the same. The AA guy then thought it was the electronic ignition, so he called relay and took us home.Ordered a new unit, and its been fine since(touch wood).
hope that helps

regards

Tony

[Stagless Steve]

A couple of observations, there is no earthing wire.
The gap between rotor and red module could be closer.
Where was the red power lead connected to?

Thanks V Mad. Isn't the black cable the earthing wire? It goes to the -ve terminal on the coil. The red power lead is connected to a white wire that comes from the feed to the inertia switch. It has been like this since I bought it 3 years ago and up until recently it ran fine. Is there something about this setup that you think might be causing it to misbehave after all that time?

[Stagless Steve]

Thats deffo your electronic ignition, I had the same as you .It cut out and backfired , then started ok and ran ok for about a month, then on my way back from a car show in Wales, it cut out and after a few minutes would start up and run for about half a mile then cut out again.Did this about 3 or 4 times,so called the AA. At first they thought it was the coil, so we fitted a spare coil I had in the boot, but it did the same. The AA guy then thought it was the electronic ignition, so he called relay and took us home.Ordered a new unit, and its been fine since(touch wood).
hope that helps

regards

Tony

From your description Tony it could almost be the same car! Does sound very much the same as what mine is doing.

Thanks to all for the comments so far. It does look like I need to put in an order for a new electronic ignition module.

[Lingen]

Steve. That is the way I have got mine wired. I think it has two advantages over connecting the red wire to the +ve on the coil. One is that in the case of an accident severe enough to activate the inertia switch, it will also cut the engine (provided the supply is from the output of the switch), and secondly it will mean that the powerspark unit will be running on battery voltage, rather than ballast resistor voltage, which should make it work more effectively. It seems to, having tried both supplies on my Stag.
Mike.

[Staggard]

In my opinion the inertia switch is not the best of contacts ( by design) and to connect it as a live feed to the ignition Even if they are well maintained and clean they can break contact unexpectedly as mine has done on a couple of occasions so now I have a LED warning light so that if it breaks contact the light comes on and gives warning at least you have a bit of grace with the fuel pump not so with the ignition.

[Staggard]

I have just had a thought it is probably illegal to have a switch of any kind that can cut the motor whilst the car is in motion as I understand it you cannot fit any kind of immobiliser that you can cut the ignition by remote control, it does not bear thinking about what devastating accident that could cause.

[Staggard]

Reading Steve's post he has said that he has the ignition connected to the feed TO the inertia switch not FROM the switch, so it wont cut the ignition if the switch fails.

[DJT]

In my opinion the inertia switch is not the best of contacts ( by design) and to connect it as a live feed to the ignition Even if they are well maintained and clean they can break contact unexpectedly as mine has done on a couple of occasions so now I have a LED warning light so that if it breaks contact the light comes on and gives warning at least you have a bit of grace with the fuel pump not so with the ignition.

We have differing experiences in this matter, Graham. I've had the Lumenition supplied by the output from the inertia switch on two Stags since I first fitted Lumenition in the early nineties. I've driven getting on for 90,000 miles in that time without the fully functioning inertia switch cutting the supply once.....

[DJT]

I have just had a thought it is probably illegal to have a switch of any kind that can cut the motor whilst the car is in motion as I understand it you cannot fit any kind of immobiliser that you can cut the ignition by remote control, it does not bear thinking about what devastating accident that could cause.

By the time the inertia switch actuates, motion has probably ceased....

[KOY 23]

I have just had a thought it is probably illegal to have a switch of any kind that can cut the motor whilst the car is in motion as I understand it you cannot fit any kind of immobiliser that you can cut the ignition by remote control, it does not bear thinking about what devastating accident that could cause.

Agree with you Graham. I think that's why the ignition feed is unfused, so as not to introduce another source of failure. Sorry Dave but I'm in the tap into the feed side of the inertia switch as they can be more unreliable than we know, masked by the inertia of the float chambers. I too never want an ignition failure, as they always occur at worst moment, which is why I used Pertronix when I had a distributor.

[Staggard]

By the time the inertia switch actuates, motion has probably ceased....

I was thinking more of a poor contact in the switch other than it being triggered which I have found not that difficult, a hump in the road that seems to a popular idea worldwide to slow you down. As been said Dave each to his own for me cutting off the fuel in a collision OK, cutting the engine don't see it, especially if there was a million to one chance it could happen on the outside lane at whatever speed. Supposing that did happen and it caused an accident what would the police and the insurance company think of this particular modification.