remove wiring loom

[mike 850]

im much more confident this time as when I had the jump lead attached it starts up, take it off and it sits there cranking again, replaced the jump lead with a nice thick earth strap so hopefully. thanks for all the help though (trying not to get my hopes up too much!)

[Jamest5r]

I think I may have it, was speaking to my neighbor and he had something similar with another car a few years back and it was an earth problem, try putting a jump lead from the negative terminal on the battery and clamp it to the block. Done this, fired up straight away, the test will be in the morning as it always struggled in the morning and slowly got to not working at all....

Result , will await the morning post

[mike 850]

Well, it started, took about 8 cranks but it started, so definitely better. the cranking was really slow but i have ran the battery down with all the messing around, gonna give it a good charge and see how it goes...

[merc85]

Well, it started, took about 8 cranks but it started, so definitely better. the cranking was really slow but i have ran the battery down with all the messing around, gonna give it a good charge and see how it goes...

Sounds like mine did :/

[mike 850]

did it just stay like that or did you solve it?

[V70 Graham]

did it just stay like that or did you solve it?

Afraid he didn't

[mike 850]

well, it let me down again this morning, although bumped it and it started first time!!! I think im on to something with the earth though, it would make sense because the coil is getting a signal when cranking, just not strong enough!! anyone know where the ecu earths? think im gonna take the inlet off, swap the starter and clean all the earthing points on the block, im also wondering if the gearbox has anything that needs a good earth?

[merc85]

God this is exactly what mine did, Earthing points two on the back of the engine at the top of the cam cover, Two on the front above the starter motor, And one on the front of the gearbox, think there is one on the front of the subframe to.

The earths are brown wires i believe which connect to the ecu. Be careful some are switchable i think.

This is where i called it a day im afraid as this sort of wiring was way above my station lol

Just one more thing, Have you checked the imoblizer ring around the igntion switch? these can act up. My car was obd1 so didnt have one.

[mike 850]

mine is obd1 too i think, 94 m plate with the a/b sockets in the engine bay? I keep reading stuff about starter motors spiking and blocking the other sensors, just bought a starter and will give everything a clean up, I WILL FIX THIS!!! lol

Cheers

[nobananas]

I did have a problem on a customers car a few years back that was similar to this. The starter motor was pulling so much current that it wasn't leaving enough for the ignition system and management. If you hooked up the coil direct to the battery it was fine but otherwise it wouldn't start. Changed the starter and it cured it. Would explain why your's starts if you bump it.

[mike 850]

yeah, its other than bad earthing its the only logical thing left, gonna clean the earthing points and run fresh wires directly to the battery too, will keep you posted. It starts instantly bumping it! everytime

[merc85]

I swapped a starter motor on it and it started 1st time ONCE! then went back to cranking and cranking, got fed up in the end as it couldnt trust it. Hence she went bye bye

[mike 850]

nnnooooooooo..... i'll give it a go, its got to be something...mines red too!

[merc85]

nnnooooooooo..... i'll give it a go, its got to be something...mines red too!

The trouble is some of the earths are common earths, and they go everywhere. Wiring was beyond me tbh and i had all the spares from two cars to play with, in the end i just ran out of things to try. And believe me i tried

[GreenMachine]

We've just had something like this on my old man's 850, - 95 obd1 - new starter motor fixed it, good luck.............

[mike 850]

yeah fingers crossed! I also have my bike if all else fails!

[mike 850]

Well, new starter motor yesterday, started 1st time. try this morning, crank crank crank!!! I can't help thinking im close as it started immediately with the new starter but something is happening when its being left overnight, I wonder if its getting any interference or I'm sure I read somewhere about rerunning the main power to the starter, any ideas?

[RiPsTa33]

Can you write a short list of what you've done as earlier you just say you've tried everything, have you changed the fuel filter?

[merc85]

Well, new starter motor yesterday, started 1st time. try this morning, crank crank crank!!! I can't help thinking im close as it started immediately with the new starter but something is happening when its being left overnight, I wonder if its getting any interference or I'm sure I read somewhere about rerunning the main power to the starter, any ideas?

Yep as id said before in a previous post, exactly what happend to mine.,

[mike 850]

I have changed:

fuel filter
fuel pump
FPR
crank sensor
cam sensor
coil
battery
Starter Motor

hard wired cam and crank sensor
crank sensor has approx 300 ohm resistance
cam sensor 0-5v
signal to coil is too weak

having taken the inlet off again I have stripped all 3 earth connections on the block and the wire looked bad on the end, fitted them all to a beefy connection to the block and also another thick earth cable directly to the battery, also got the wire brush on the earth connection to the gear box, it looked ok until i cleaned it (its supposed to be brass) its nice and clean, put it all back again an instead of 8 cranks it fired on what felt like half a turn, it must be something to do with the earth.

pretty sure its not a component as you can bump the car and it fires straight away, will see if what I have done today works tomorrow