Andy K or anyone, please help with starnge electrical problem

[TOBYC]

Ok when i came out of work yesterday my car had a flat battery. I borrowed a battery from work and got home no problem. When I got home I was changing over batteries again and I could hear a feint buzzing sound which I can only descibe as being like a scalectrix transformer type sound. This sound is loudest when you put your ear on the top of the plenum chamber........and occurs when the ignition is off??

I unplugged the ecu and it stopped, plugged it back in and it buzzed again.......basically i have narrowed it down to a plug which if you disconnect, the buzzing stops.

If you follow the loom from the fuel rail at the gearbox end the first plug you come to is a two wire plug with a black and yellow wire and a plain black wire if I remember rightly, then follow the loom down about another 2 inches and you will come to a 5 wire plug, this plug is thin and about 1.5" wide and 2.5" long with five wires going in and five coming out.........

Red with blue tracer
Brown with blue tracer
Brown with red tracer
Brown with black tracer
Brown with white tracer

This part of the loom then follows the black plastic water hose which runs behind the block. When I unplug this plug, the buzzing stops and im presuming the buzzing sound has something to do with my battery drain??

I know there is an oil pressure switch and knock sensor and idle valve down there but how can I find out what is causing this, what do those five wires go to? and how can i check to see whats wrong.

I gave Rob (RDS) a bell last night but it seems his loom is slightly different to mine as he couldnt find the plug.......... His is an M reg turbo engine and mine is a K reg 92 turbo engine.

Can some one help please before something goes tits up and I cant get to billing or summat........

last night and this morning at work ive unplugged the wires so it wont drain my battery hopefully

Thanks Guys and Gals much appreciated


Toby

[TOBYC]

ok ive just been ut to the car park to have a check on me mota........... something else is strange............ the air flow meter metal housing is very very hot.....and the car hasbeen parked up for an hour............ i can touch the turbo but barely touch the airflow meter.....???

this is starting to worry me now............ i have unplugged the ecu and the airflow meter.............

the buzzing was definitly not coming from the airflow meter though.............

help im desperate.......

[TOBYC]

just been out to me mota again.......... since ive unplugged the airflow meter and the ecu, the ecu and airflow meter have cooled down........???

would i have a constant live to my engine loom some how??
how would i find out where its coming from..........??

i hope im narrowing it down a bit for you lot to help me.........

[AL_P]

well ur fecked lmao

try finding the source of the sound and well u could find the prob

as u can tell i dont know much

[TOBYC]

yeah but it seems that my whole engine loom is live even with the ignition switched off....... so the buzzing would be a red herring as everything would be live anyway.......... thats why my airflow meter is hot cos there is no airflow through it to cool the hot wire............

so i have to find out how the engine loom is staying live

[LEE69]

is it just the engine loom live or are things live in the car i e dash?

maybe the ignition barrels had it

[TOBYC]

just been out to me mota again..........and tuffty met me in the car park to check some stuff out..........

basically the engine loom is live but the rest of the loom in the car etc is still swiched with the ignition barrel so thats ok.............

ive connected everything up again in the drivers foot well and under the bonnet and just taken off the big black and white wire from the battery which it the main live to the engine loom........ so obviously the engine bay loom is now off.

do you think the big relay in the drivers foot well is knackered and is not switching the engine loom off???

if the relay is shagged, what could have caused it ???

any help please???

[TOBYC]

bttt

[Giles]

I had a similar problem with a cav diesel I had years ago. Battery would drain, car wouldn't start, weird dash lighting effects, switches that wouldn't work.

Got a pro round to look at the wiring and he found that one of the main earth straps from the battery to the chassis (or to engine can't remember which) had broken. He said this is quiet a common fault on car wiring and can lead to all sorts of strange going ons. Therefore I suggest looking round the wiring to see if you can spot any dodgey earths that are )or could be) broken. Replace wire and see if that does it.

[TOBYC]

cheers lad will do.........

[TOBYC]

doh.bttt doh!

[Andy K]

I would replace the fuel pump relay if you have one. (as you say drivers footwell)

Check to see if the red/blue wire is live on the Air meter when you have the problem (with the ignition off)

[TOBYC]

cheers Andy...........I checked everything again last night........... it seems the big relay )presumably fuel pump relay) blew and would not switch off the engine bay loom............. i replaced the relay and it seems fine now (touch wood)


hopefully all is well now........... cheers