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Electrical Gremlins
Furyous - 14/1/17 at 07:21 AM

I've just finished rewiring my Fury and I'm much happier with it all. I fired the engine up today and it seemed to be running great apart from a problem I had before. At around 3,500 rpm the electrics go screwy. The speedo dial jumps up, temperature gauges blip. If I watch TunerStudio while I'm revving it the temperature will blip to well over 100*c, and Microsquirt will do its stuff to counteract that for the split second it happens. If I hold the revs around 3,500 it will continue being screwy.

Not sure where to start with this one. Interference from EDIS? Alternator playing up?


snowy2 - 14/1/17 at 08:00 AM

have you tried to fit suppressors to the alternator? (capacitors fitted between the lives and earth?)
much like we had to do in the old days for fitting stereos into cars......


Furyous - 14/1/17 at 09:32 AM

That could well be the problem. I'm using an Integra alternator, which I don't think have suppressors as standard. I'm pretty sure I have one in my box of bits somewhere, but what kind of rating would I need? It's a 90 amp alternator.


bonzoronnie - 14/1/17 at 09:49 AM

I believe 2.2uf is the most common value capacitor used for modern alternators.


2 Car Radio Noise Interference Coil/Alternator Suppressors 2.2μF Classic Vintage


Furyous - 21/2/17 at 09:50 PM

Coming back to this, I couldn't find one in my box-o-bits so I had to buy one. This being New Zealand, things are either hard to find or stupidly priced. I ended up buying one on ebay and waiting. In the mean time, the problem seemed to have sorted itself, which is always a worry. :p The capacitors finally turned up yesterday after about 6 weeks so I installed one. There doesn't seem to be any ill effect so maybe it will at least stop any problems coming back in the future.


David Jenkins - 21/2/17 at 10:28 PM

Could it be a loose connector somewhere? OK at low revs but rattling around when the engine starts vibrating strongly? I'm thinking of things like the alternator connector, which has springy terminals inside that may have got bent or lost their springiness.

I'd be tempted to round all the important connections to see if anything isn't as tight as it should be...


dave36 - 28/5/17 at 08:39 PM

if you have updated the firmware it could be the "soft" rev limiter, mine was at 3500 - its now at 6500