That's strange - electrical gremlin help

[Moto]

Sitting at traffic lights and suddenly my volts, temp & fuel gauges all dropped to zero. Rev counter started jumping zero to 1,500 revs and the ignition light started flashing on/off. It lasted for about 20 seconds in which time the engine was idling perfectly normal. I pulled forward when the lights changed and everything when back to normal. Got home an hour later with no further problems at all.

What happened .... any suggestions?

[RCK974X]

First thought - loose connection somewhere.

Second thought - if you have a classic generator (pre-alternator), the control boxes can flicker in strange ways (they have several relays inside) and may be an indicator that it's failing....

third thought Fuse ? If there are any......

But given it's a TVR, I'd go with dodgy wiring as my most likely choice !!

[Slow M]

As above, plus:
Does your car have a similar voltage stabilser, as the M-series cars have behind the dashboard?

Best regards,
Bernard.

[tomtrout]

All those guages have a common linked earth. That would be where I would be heading.

[Dollyman1850]

Just wiring dash now and the dash gauges and dash lights have a looped earth..Head downstream of the faults and you will find the problem.
it will be an earth or a dodgy power looped connection….however a power fault would only affect 1 gauge so I would go earth first.


N.

[Moto]

Thanks guys. A few things to go at so will let you know progress.

[Moto]

Sorted.

The rear side light bulb holder had sprung itself out of the fitting. Pushed it back in, 110 miles later all perfect. Hard to be sure but I guess it was touching something it shouldn't have been.

I'll know what to check first next time my gauges start doing strange things.

Moto