Very weak spark...

[Tomf]

Well iv got everything wired up no, but when i turn the engine over im getting a very weak spark not even visible at the plugs when there removed...

The only reason i know they are sparking is because i fitted my inline plug testers between the plug and HT lead and i can see the weak spark.

Has anyone got any idea what iv done wrong to get such a weak spark?

[NITROPIXIE]

Thats does sound quite weak. I can easily see the spark on mine in daylight.

Are your HT leads new as these could of broken down??

How old is you coil pack??

Have you got a good/decent earth from your engine to your car battery???

Have you got a good earth for your coil pack/edis unit??

Have you used a resistive wire (which is sometime used with a single coil) as a power supply?? Have you used an adequately sized power lead??? Are any of the ground/power wires getting hot??

[BRUCEROE]

My guess, you have a defective coil, or possibly a poor 12V power connection. Bruce Roe

[Tomf]

Thanks for getting back to me, iv had a little play with it today, and found the coil was getting a vary low voltage coming in, as im using a hard rev-limiter i was told i take the live feed from one of the pins off the megajolt unit, so i decided to try and take a live feed for this directly off a battery, and by doing this i got a lovely strong spark, and i managed to fire up my new engine for the first time.

So now i guess its running off the EDIS 4 but it seems to only be running on 3 cylinders... The only thing i can think off is my CPS might be slightly out, but this can only be a max of 10* as when i put everything together i couldnt remember if you positioned the crank sensor 9 teeth before the double gap of 9 of the dividers...

But surely this wouldnt make it run so bad as as if i run my distributor run 10* out it seems to run reasonably well still...

[Tomf]

Also as the Megajolt unit is giving such a low output could this mean that its buggered inside?

[BRUCEROE]

Of course you know about where cylinder #1 should show on the timing mark. The others should be delayed a known amount. A good first check, is use an inductive timing light on every plug wire, to make sure the spark happens about the right time for that cylinder. The timing mark will be illuminated that much farther around the rotation. This worked well on my odd fire engine. Bruce Roe

[Tomf]

Hi thanks for the reply, yes iv double and tripple checked the leads are correct, my main concern at the moment is the fact the megajolt unit isnt giving the correct voltage output for the hard rev limiter (coil power supply)

+ the fact i cant get megajolt to connect up with my laptop, but i feel thats more of a cable issue.

[vermale]

When I first start my engine with Megajolt I've tried to see sparks but nothing append, later I've tried with a stroboscope lamp and I saw ignition working fine.
For me if you have no spark it's not a Megajolt problem because Megajolt is just suppose to change advance except if you have also the rev limiter who can cut EDIS.
First think to do is to have a full loaded batt to makes the test; you can use your charger at the same time.
You can also try without the Megajolt with EDIS and COIL and see if you have sparks but verify it with stroboscope it's more sensible.