mk2 vr6 starting/ignition problem - problem fixed!

[cняis]

hi guys, hope you can help!! 

mk2 vr6 OBD1 engine with post 90 fusebox. fuel pumps prime off a seperate switch. push button starter.

Problem is, the car is taking a while to fire up. It used to start 'on the button', but now its taking a lot longer. It will fire eventually, after about 10 seconds or so, and runs fine otherwise. its a bit worse when its been left overnight. fuel pumps prime ok and engine turns over fine.

Im not sure if this is related but when ignition is switched to pos 2 the dash lights take about 3 seconds to illuminate properly, and I often get a buzzing sound coming from the fusebox as if a relay is breaking down. I traced it to no. 4, ignition relay. I have swapped the ignition relay with a known working one (relay 4) and still no joy. The fusebox needs ripping out and earths need sorting anyway as despite having a healthy battery, im getting about 9 or 10 volts everywhere when running.

any clues guys? possibly cam/crank sensor or something? or a bad earth/bad fusebox connections/faulty ECU relay? shes driving me mad!

[rubjonny]

I'd check the ignition switch first, nothing to do with the engine will effect the slowness of the dash lights to come on. sort that issue before you worry about the rest of it, cant be helping anything thats for sure

[cняis]

I'd check the ignition switch first, nothing to do with the engine will effect the slowness of the dash lights to come on. sort that issue before you worry about the rest of it, cant be helping anything thats for sure

or more importantly wiring to/from the igniton switch to the ignition relay (relay no 4)?

the relays only click into life once the dash lights are at full brightness (3 or 4 seconds)

also everything dims for a couple of seconds when you switch the lights or blower on, engine running or not

[cняis]

ignition switch only seems to get 10 volts, drops to about 5/6 volts when cranking, obviously everything dims a lot and eventually the clocks and alarm reset. this is whilst cranking with ＆ without ignition on (as the starter button is perminantly live).

although it fired up fine on friday afternoon, its now dead! it just will not fire. does this sound more like an earth issue, as the relays take a while to come to life plus the clocks reset?

[tonysmallwood]

cant help u to much im sorry to say as when i done my mk2 vr6  i used the vr6 fuse box and as much of the loom i could maybe its time for u to change it

[rubjonny]

there is no relay for the ignition, #4 disables the wipers, blower etc while the car is cranking over on the starter.

I'd start by checking the wiring to the switch, and the push button starter. make sure everything back there is ok. obv check your battery is ok as well

[cняis]

RJ you were right to suggest checking the feeds, as its all sorted now.

it was an issue with the battery terminal block in the engine bay (battery is located in the boot, and theres a BMW battery cable running up the car into the engine bay with a BMW multi terminal block on the end).

there are 4 terminals on the block, 2 main and 2 secondary. the 2 main terminals are hard wired to the battery cable, but the seconday terminals need to be bridged off the main ones to work.

the wire bridged to the 2 secondary terminals was too thin so it burnt out. the main wiring loom was powered from one of the seconday terminals and was only getting 10v at best  :shock:  of course this 10v took a dive when it was being cranked over!

all sorted now and starts a treat    plus everything running off the main loom is actually getting 12v and not 10v so my lights are brighter and so on