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Missing at speed?

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Hi Doug

I got 2.85ohms on measure. So hooked everything up - with new ignition leads - and with the first turn of the key she fired up - having stood for a week!

I will let you know if the original problem is still there - but for now she is running sweetly.

Thanks for all your help.
 
2.85 Ohms is basically a standard coil. You'll have a much hotter spark now without that additional ballast resistor.

After you've driven the car for a few days be sure and post back and let us know how it's running.
 
I have driven the car now for 5 days or so and the original problem has not recurred! Yahoo!! However, I have noticed that the difference between the brightness of the headlights at idle and above 1000 rpm is substantially different. Last night I drove through a rain shower - I had the headlights on and the wipers going. The wipers were quick while running and slow while idling - again a substantial difference.

I have had the car at an auto sparky twice. He is adamant that the alternator is not overcharging - said I would now if it was as the battery would start to give of a sulphorous smell.

This normal? Any advice? You think I am just being paranoid?
 
Well, you say it's running better and that is the good news.

I have a couple of suggestions for you that will be interesting little side projects.

First, either buy a new volt gauge or look for a nice used one on eBay. Look for VDO if you can find it (not Smiths). The VDO gauge will respond quickly to changes in voltage while the Smiths has VERY slow response. Once that's wired in, glance at it periodically while you're driving... particularly when you notice the headlights dimming. It might just be a minor fluctuation in the car's operating voltage that is the issue. However, you'd really like to see the car's charging system operating at 1V to 1.5V over what the battery shows with the engine off. You do not want to see alternator output higher than about 14.5V

The other project that may help with the headlights (possible... but harder on the wipers) will be to make and install a headlight relay panel. There are kits out there for this but you can easily make your own using Bosch/ISO relays. These relays are regularly available at auto parts stores and online from surplus companies like bgmicro.com. The advantage of adding the relay panels is that the supply to the lamps is more direct through low resistance contacts. Most people report consistently brighter headlights with relays installed. The relays also take the load off your dash wiring and standard headlight switch. This extends the life of those parts.
 
Thanks Doug.

I have already put my headlights onto relays. So the switch activates the relay and pulls the juice directly off the battery as opposed to through the switch. I have also upgraded my headlights to take a modern H4 fitting and I am running 60/55 xenon globes. The lights on my Mini are excellent - I would venture to say as good as my late model BMW.

I will take your advice and put in a volt gauge. Will get back to you and let you know.
 
Something weird happened.
I posted a comment, came back an hour later and its gone??

Anyway here it is again.

I have ordered the VDO Voltmeter. In the meantime I borrowed a temporary setup from the auto electrician - I think I am driving him mad!

Before starting the meter measures 12.2V. On starting (before revving) the needle flicks to about 12.8V after about 2 seconds. Revving the engine and the needle jumps to about 14.4V. And sits there more or less consistently even with headlights and wipers on. So it seems I was being over cautious - but better safe than sorry :smile:

I will still install the voltmeter - so I can always be sure.
 
Everything sounds OK to me.

I had a similar posting problem about a month ago. Very frustrating indeed.
 
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