New Megajolt Install - No Spark and 0 RPM Readout

EDIS and Megajolt installation related topics. Be sure to review the <a href="http://www.autosportlabs.net/MJLJ_V4_vehicle_installation_guide">Vehicle installation guide</a>

Moderators: JeffC, rdoherty, stieg, brentp

Post Reply
Jackiefan
Posts: 3
Joined: Thu Oct 30, 2014 12:46 pm

New Megajolt Install - No Spark and 0 RPM Readout

Post by Jackiefan »

Hi All,

I've got a little problem with my new Megajolt install. This is the first time I've used megajolt so forgive me if these questions are basic but here goes...

The engine is a 1.8 MKII MX5 Motor and for the ignition we are using the standard MX5 coilpacks.

Wired everything in according to the instructions and diagrams.

As far as I know my EDIS module is not faulty although I've got a second one on order just incase

I can connect to the Megajolt, read/write configuration without issue.

When cranking the car, we don't appear to have a spark and the RPM Readout on the megajolt software stays at 0, however the RPM on the dash reads around 280. The Dash gets its RPM signal from the megajolt and not from the EDIS.

Is this normal for the Megajolt not to display RPM when cranking?

I haven't tried just running on the EDIS because this is a brand new engine build and obviously the first start up is the most important and I'd rather it ran correctly rather than "limp home".

Let me know if anyone has any ideas.

brentp
Site Admin
Posts: 6274
Joined: Wed Jan 24, 2007 6:36 am

Post by brentp »

One of the biggest culprits on a fresh install is reversed wiring on the VR sensor. try flipping the polarity and see if that works!

Also see the very helpful verification steps, here:
http://www.autosportlabs.net/MJLJ_V4_ve ... tion_Steps

Please let us know what you find out!
Brent Picasso
CEO and Founder, Autosport Labs
Facebook | Twitter

Jackiefan
Posts: 3
Joined: Thu Oct 30, 2014 12:46 pm

Post by Jackiefan »

Still no Joy i'm afraid. We've rewired it, and checked everything at least twice and replaced the EDIS. Tried to run it both on standalone EDIS and with MJ plugged in.

We dummy rigged the Coils to a battery and it appears the Signal wire needs a Live to generate the spark, Is this to be expected? I kinda thought it would need to see a signal to ground.

Also just to confirm I am using standard MX5 1.8 coil packs, is this ok?

Any help is appreciated.

Jackiefan
Posts: 3
Joined: Thu Oct 30, 2014 12:46 pm

Solved!

Post by Jackiefan »

So it turns out you cannot use MK1/2 MX5 1.8 coils with the megajolt setup wired as it is in the instructions. I guess the Coils need some extra wizardry.

I shot out today and picked up a Ford coil pack, wired it all in and the car started on the button. Considering it had a finger in the air 2D advance map it ran beautifully and if I had just gone with the Ford coil pack from the start installing and configuring the MJ would have been a total cake walk.

Dead impressed with the MJ and thanks for trying to help with the teething issues!

If anyone has a decent 3D map for a high comp 1.9 4 pot similar to the MX5 engine then I'd love to take a look at it.

brentp
Site Admin
Posts: 6274
Joined: Wed Jan 24, 2007 6:36 am

Post by brentp »

That's great, thanks for the feedback!

Take a look at the ignition map library to see if anyone has something similar. Nothing beats a dyno / rolling-road session for tuning an ignition map, though!
Brent Picasso
CEO and Founder, Autosport Labs
Facebook | Twitter

Post Reply