No Spark

[laurenlee99]

Hi there,
Ive just bought a 1.9 panel van that has had new coil, plugs and dizzy etc fitted before i got it but still does not want to spark unless i put a lead from the top of the coil to the engine block. After i have done this it will start on the button for half a dozen times then i will have to do it again... any ideas please???
many thanks
Tommy

[Whitevanman]

Bad earths?

[laurenlee99]

I've tried to put a thick earth from chassis to engine block but it still didn't fire. Could it be a coil fault? Haven't really got the cash to call a mechanic at the mo and I'm sure it must be something and nothing as it runs sweet as a nut when it fires?? Help please!

[1664]

When you say "top of the coil to the engine block" do you bean the metal body of the coil?

[laurenlee99]

No, on top of the coil is a terminal with 2 green wires, I put it from there to the engine block and it sparks a few times but then fires. I can remove the wire and it will start fine for 5 or 6 times then will go dead again! Frustrating! Thanks for answering.

[1664]

There's an earth point below the coil with a brown 1.5mm cable attached. Try removing. cleaning and reattaching. Also check connection at the other end of it which is terminal 2 of the 'TDI Control Unit' (whatever that is ). Also, while it's disconnected, check the continuity if you have a multimeter.

This is just a guess based on the wiring diagram by the way

EDITED due to truly abysmal spelling

[laurenlee99]

Thanks will try that now!

[laurenlee99]

Right, I've just tried the brown earth under the coil to the brown earth on the engine block and have continuity .
I've just tried the wire thing again and it starts and runs great... After a while of stopping and starting, I have to do it again or it won't spark?? I'm sure I'm just missing something...

[1664]

Right, I've just tried the brown earth under the coil to the brown earth on the engine block and have continuity .

Did you do it disconnected and to the other end on the TCI unit?

after this I'm out of ideas other than swapping out components

[laurenlee99]

Is the tci unit the flat thing with the flat plug attached to the bottom of it? Sorry for being vague!

[1664]

Looks like this apparently
http://www.vwheritage.com/vw_spares_TCI ... 198926.htm" onclick="window.open(this.href);return false;

The coil connection you are earthing is the negative side of the coil's primary which is connected to the TCI. The TCI is itself earthed via pin 2 to the earth point below the coil via that brown cable. Like I say it's a guess based on the wiring diagram on Page 12.23 of the Haynes manual.

[1664]

I think it's the object mounted on square silver plate on the engine bay wall just to the front of the coil in this picture (I think)



hopefully someone can confirm this.....