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Ah yeah, good point. Haha

you may have to measure the base current with an ocilloscope using a current probe (similar to a tong ammeter). The transistor requires a 0.6V signal to be applied to the base to switch it on but if for some reason the circuit resistance may be too low, this will increase the current. This current (base emitter) and the current from the coil (collector emitter), flow through the transistor emitter to ground. Coupled with the fact you are running wasted spark which in theory will double the current may increase the problem a small rise in the base current can have. The ecu should have current limiting resistors fitted to the ignition driver outputs to limit this. Proper testing with the right equipment will be required to prove each circuit is correct.

We run the same ecu/coil/igniter/dwell in our circuit car and have not had an issue.

Edited by DiRTgarage
  • 2 weeks later...

Quick update: I'm back at work in New Caledonia now. Before I left I cut open another ignitor that the car had fried. It also had a dead ground connection. This time it was not the track that was burnt out, but the little piece of wire that connects the PCB to the terminal. I soldered a bit of wire in its place, so now I have a spare ignitor. Fingers crossed, the car doesn't play up on my wife while I'm away.

Quick update: I'm back at work in New Caledonia now. Before I left I cut open another ignitor that the car had fried. It also had a dead ground connection. This time it was not the track that was burnt out, but the little piece of wire that connects the PCB to the terminal. I soldered a bit of wire in its place, so now I have a spare ignitor. Fingers crossed, the wife doesn't play up while I'm away.

fixed :)

Edited by DiRTgarage

I'm running a Vipec, but hundreds of people are running this or a Link without a problem, so very strange... I had the Vipec on the car for 7 months without a problem and then the car fried 3 modules in 4 months, so I don't think the ECU is to blame. I've emailed Ray Hall (Vipec) all the details and he was quite helpful. He asked his engineers to look into it and they couldn't see any problem from their end. He's even offered a replacement ECU free of charge, just in case, but he's quite confident it's not an ECU issue.

I've now disabled overrun fuel cut, just in case this was causing the issue. As I mentioned above, I believe that all 3 times the module failed during similar circumstances (coasting down a hill). It's probably just coincidence. Ray doesn't think overrun is an issue and many Vipec users have it enabled without any problems.

Now I've got a thick piece of wire in the ground circuit of the ignitor, so with any luck it won't blow again. Well it may not be the ground connection that fails next time, but perhaps something else will fail... Time will tell

  • 3 weeks later...

Quick update: It has been running fine with the fixed ignitor module. I swapped in the 2nd module that I fixed and that one runs fine, too :)

Ray Hall sent down a new ECU last week and I swapped that in with no problems. It was bloody good of them to send a replacement even though they don't think it's an ECU problem. Now just keeping fingers crossed...

  • 1 year later...

I am not an electronics guru at all, but this may help, or not, but I shall post it anyway :thumbsup:

I have an RB26 engine running a Motec M800 ecu here in the UK. It runs the coils individually, as stock, not in wasted spark format. It started eating stock igniter boxes nearly straight away, and all were new ones. The symptoms were it would be fine until I took it on track, and after say 6 laps it would start to miss. By the time I got it back to the pits it would have dropped at least one cylinder. Let it cool, or fit another igniter it was OK again. I got through 3 new genuine boxes, and the cost was getting ridiculous. My mapper, an ex Motec Australia guy called Dave Rowe, took some dwell out and it seemed to fix things, but I never felt it ran as strongly through peak torque. I got two Bosch triple igniter modules. I chose those beacause I could borrow them off my Volvo V90 road car, it has two for its straight six lump, and because Motec had the pinouts for them. I extended the wiring away from the ludicrous place Nissan put the stock igniter, over to the RH inner wing and mounted the Bosch igniters on a nice big alloy heat sink, bolted in turn to the inner wing sheet metal. I turned the dwell back up and the car has done lots of track days and many hours trouble free running, The Bosch igniters barely get warm. I would use these igniter boxes on any other RB engines I build now, they are cheap, have readily available new connector shells and contacts, and they fixed my issues. I am now toying with having a look inside one of my stock Nissan boxes, but my problem was heat related and intermittent. Could a burnt track act that way?

Great forum by the way, some serious technical issues are addressed and usually soundly beaten :)

Edited by Chris Wilson

Chris

The igniter failures that BoostedBarge and I (documented here http://www.skylinesaustralia.com/forums/Vi...0&start=20) have experienced have been when coasting to a stop to negotiate a junction or similar, and always sudden and final as once the earth cct is gone, nothing works. No missing etc to indicate a problem. Sounds to me like one of the relays in yours is failing, hence the miss.

Does it get real hot? I had an ignitor kept getting really hot, though it never blew like yours, tried earthing but made very little differnece. It turned out to be a tiny bent pin in the ecu giving low voltage.

Luckily I had a smart bloke on the job cause I doubt I ever would of figured it out.

Not sure if this is related but just thought Id share..

Edited by Arthur T3

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