Thread: Help please

Originally Posted by Nathan78

Thanx mike
Well put a test light and multi meter on the coil + side and got no power at all now ???
It did throw a spark as I said but now she won't even do that
The machanic that looked at it was a RACV bloke talking to a LR mate of his on his phone
Why would I not be getting power to the coil ?

Having determined the 12V supply to the ignition coil is faulty, check the plain white wire from the back of the ignition switch (ignition feed) to the underdash fuse box (in a black sleeve, open as necessary). If power appears here with the ignition on look further downstream, ie alarm spider or bridging plug. The distributor is easy to check, put a multimeter on ohms across the pickup wires, they are in the red and blue pair at the lucas amp. You should get a constant resistance reading of around 3K ohms if it's the same as my spare dissy, then if you move the rotor so the reluctor teeth pass the pickup it should make the resistance reading dance around as some small voltages are generated. With the dissy stationary the resistance should stay stable as you wriggle any plugs or cables between the dissy and amp.

Ok cool
I have power in the fuse box coming from the ignition
Checked the red and blue wires at the amp on the rad support and got 3.3 ohms on the 200k setting on the multi meter
Is this right so far ?

Originally Posted by Nathan78

Ok cool
I have power in the fuse box coming from the ignition
Checked the red and blue wires at the amp on the rad support and got 3.3 ohms on the 200k setting on the multi meter
Is this right so far ?

Yup (BTW it's 3.3K ohms or 3300)

Also the best way to run a temporary feed to the ignition coil is to run direct from the ignition switch/fuse box to the (+) coil terminal. That way the wire can be left in place and the car will safely drive.

Once you have guaranteed power at the coil (+) use your test light at the negative coil post and crank the engine. Light should pulse down if the pickup and amp are correctly working. If you get the pulsing but no regular spark, chuck another coil on it.

ok well ran a power wire (just from battery for now)and had 13.2 volts on both sides of the coil
once i cranked it the neg side droped down to 10 volts
going to try my spare coil now

btw i looked at the spider and its not their
from what i can see it has been bypassed with a LR loop harrness

ok swaped coils with my spare and still ****ing spark coiming out the coil

Originally Posted by Nathan78

ok well ran a power wire (just from battery for now)and had 13.2 volts on both sides of the coil
once i cranked it the neg side droped down to 10 volts
going to try my spare coil now

btw i looked at the spider and its not their
from what i can see it has been bypassed with a LR loop harrness

All you are doing with the meter is measuring your battery voltage while cranking. 10V is about right while the starter is engaged. You need a test light to see the negative side of the coil being pulsed. If there is no pulsing your ignition amplifier is either dead or not getting an input signal from the dissy. (Did you test the resistance of the pickup and move the rotor as I described earlier????) Think of the amp doing what a set of points does, open and close so the negative side voltage of the coil goes up and down each time the coil fires.

Those Lucas amps are notorious for dropping dead. I use a Bosch module instead, needs a bit of skill to fit and get working properly. Link to post describing this mod to a D1:

Lucas ignition amplifier replacement by Bosch 024

sorry i miss read what you said (i think getting frustated)
ok retested the pick and ohms are good at 3.3k and dance when rotor moved but return stady when not
also got a very very small volt come though
rechecked coil all good but no pulse

i have already replaced the modgle

OK if the amp/module is new, did you connect the plain white wire from it to the coil positive and securely bolt the assembly back into position, making sure heat sink paste was used under the amp, screws clean and tight, if all that was done OK then the replacement amp/module is faulty. Wouldn't be the first time.

PM me your address, I can send you a couple of old ones to try, I wouldn't trust one myself but it might work for you.