hello, I've recently been having problems with my 1.8 ecotec engine.
it all started when i noticed that when i turned the key in the ignition to phase one the fuel pump would wherr away for a second as its suppose to but now for some reason the fuel relay keeps clicking on and off randomly at exactly the same time as the fuel pump down the back on the car. to try and cure this problem i changed the fuel relay and checked out the earth for the relay on the inlet manifold. that did nothing at all! took the earth off and turned the key and the relay just gave out a fast buzzing sound which is what its suppose to do. i even tried relocating the earth but it still does the same thing. on phase one when the key is in ignition, if you go into the engine bay you can hear the fuel being pumped in intermittently as well and the idle valve control humming continuously. the engine runs but dies almost instantly and is hard to start.
I had a friend who is a really good mechanic and electrician come round today to try and figure out the problem armed with a wiring sensor and we discovered that a little green and brown wire attached to the relay keeps fluxing in power. when earthed the relay seems fine but then power comes in and it cuts out including the fuel pump. i've tested the fuel pump thats fine and tested relay and thats fine apart from that wire. does anyone have any idea why it is fluxing?
sorry if this is boring you!