Strange whirring sound - HELP !

[mohitos]

Hi guys

Just got the car back from TVR Power after a lot of fettling to make it run smoother. That's all gone very well but I now have a strange pulsing whirring noise when the ignition is switched on. If I start the engine the noise continues. The whirrs last a couple of seconds and repeat every 8 seconds.

It seems to be coming from underneath the dash somewhere, possibly down by the ECU. It was dark but I've taken a video to try and catch the sound it's making. Is anybody familiar with the problem ?

[Griffinr]

Sounds like the fuel pump and the click of the pump relay which is under the glove box. Difficult to judge the direction of sounds sometimes.
Rob.

[mohitos]

Thanks for that. I agree the sound does seem like that of the fuel pump. Direction seems wrong though. I'll take another look tomorrow and stick my head in the boot.

If it is the fuel pump, any idea why it would continue to prime, even when the engine is running ?

[Loach1]

The pump should prime for a second with ignition on, then run constantly with engine running. There isn't much near the ecu, just a couple of relays and the wiper motor. Could it be the wiper motor on intermittent, but mechanically disconnected? Or maybe some aftermarket gadget?

[mohitos]

Loach1 said:

Could it be the wiper motor on intermittent, but mechanically disconnected?

BINGO!

What a monkey moment !

The windscreen is half way through being replaced and the fitter had left the wiper arms off overnight.

The trimmer had knocked the wipers into intermittent when fitting the cowl yesterday.

So I was getting the buzzing every 8 seconds but no visible action.

What a plonker but relieved there's nothing wrong.